diff --git a/README.md b/README.md
index ca1126540..4e83502ba 100644
--- a/README.md
+++ b/README.md
@@ -388,6 +388,12 @@ specified page; e.g.:
 
 	http://localhost:8088/?aspect=2.0
 
+- *resume*: set it to a numeric value (0-3) to override a machine's *resume* setting; e.g.:
+
+	http://localhost:8088/?resume=0
+
+More information about the *resume* attribute is available in the [documentation](/docs/pcx86/computer/#attributes).
+
 Updating PCjs
 ---
 
diff --git a/_posts/2014-09-30-pcjs-coding-conventions.md b/_posts/2014-09-30-pcjs-coding-conventions.md
index 445e5c654..0317ecf4c 100644
--- a/_posts/2014-09-30-pcjs-coding-conventions.md
+++ b/_posts/2014-09-30-pcjs-coding-conventions.md
@@ -81,10 +81,10 @@ However, I've gradually switched to the more conventional JavaScript object nota
  
 ``` javascript
 ChipSet.PIC_LO = {
-	OCW2_EOI:           0x20,           // non-specific EOI (end-of-interrupt)
-	OCW2_EOI_SPEC:      0x60,           // specific EOI
-	OCW2_EOI_ROT:       0xA0,           // rotate on non-specific EOI
-	OCW2_EOI_ROTSPEC:   0xE0            // rotate on specific EOI
+    OCW2_EOI:           0x20,           // non-specific EOI (end-of-interrupt)
+    OCW2_EOI_SPEC:      0x60,           // specific EOI
+    OCW2_EOI_ROT:       0xA0,           // rotate on non-specific EOI
+    OCW2_EOI_ROTSPEC:   0xE0            // rotate on specific EOI
 };
 ```
 
@@ -104,7 +104,7 @@ To ensure that debug-only code is not simply *disabled* but also *removed*, the
 
 ``` javascript
 if (DEBUG) {
-	[code to be removed by the Closure Compiler]
+    [code to be removed by the Closure Compiler]
 }
 ```
 
diff --git a/devices/pdp11/machine/1170/panel/debugger/README.md b/devices/pdp11/machine/1170/panel/debugger/README.md
index 256f8066a..fd36680e3 100644
--- a/devices/pdp11/machine/1170/panel/debugger/README.md
+++ b/devices/pdp11/machine/1170/panel/debugger/README.md
@@ -6,6 +6,7 @@ machines:
   - id: test1170
     type: pdp11
     debugger: true
+    sticky: top
 ---
 
 {% include machine.html id="test1170" %}
@@ -46,8 +47,62 @@ Debugger commands described below to load and execute these "toggle-ins".
 	Load Address 300
 	Exam                Display = 070707 ... Relocation works
 
-With the PDPjs Debugger, the above "toggle-in" is easily entered with the following commands (the semicolons are optional;
-they just make it easier to paste an entire set of commands into the Debugger at once):
+Step 1: Load ADDR register with 200:
+{% include machine-command.html type='clickOnce' label='LOAD 200' machine='test1170' command='script' value='set Panel SR 200;toggle Panel LOAD' %}
+
+Step 2: Deposit 012737 at ADDR 200:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 012737' machine='test1170' command='script' value='set Panel SR 012737;toggle Panel DEP' %}
+
+Step 3: Deposit 000400 at ADDR 202:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 000400' machine='test1170' command='script' value='set Panel SR 000400;toggle Panel DEP' %}
+
+Step 4: Deposit 177572 at ADDR 204:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 177572' machine='test1170' command='script' value='set Panel SR 177572;toggle Panel DEP' %}
+
+Step 5: Deposit 012737 at ADDR 206:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 012737' machine='test1170' command='script' value='set Panel SR 012737;toggle Panel DEP' %}
+
+Step 6: Deposit 070707 at ADDR 210:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 070707' machine='test1170' command='script' value='set Panel SR 070707;toggle Panel DEP' %}
+
+Step 7: Deposit 000200 at ADDR 212:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 000200' machine='test1170' command='script' value='set Panel SR 000200;toggle Panel DEP' %}
+
+Step 8: Deposit 000000 at ADDR 214:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 000000' machine='test1170' command='script' value='set Panel SR 000000;toggle Panel DEP' %}
+
+Step 9: Load ADDR register with 300:
+{% include machine-command.html type='clickOnce' label='LOAD 300' machine='test1170' command='script' value='set Panel SR 300;toggle Panel LOAD' %}
+
+Step 10: Deposit 300 at ADDR 300:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 300' machine='test1170' command='script' value='toggle Panel DEP' %}
+
+Step 11: Load ADDR register with 17772300:
+{% include machine-command.html type='clickOnce' label='LOAD 17772300' machine='test1170' command='script' value='set Panel SR 17772300;toggle Panel LOAD' %}
+
+Step 12: Deposit 077406 at ADDR 17772300:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 077406' machine='test1170' command='script' value='set Panel SR 077406;toggle Panel DEP' %}
+
+Step 13: Load ADDR register with 17772340:
+{% include machine-command.html type='clickOnce' label='LOAD 17772340' machine='test1170' command='script' value='set Panel SR 17772340;toggle Panel LOAD' %}
+
+Step 14: Deposit 000001 at ADDR 17772340:
+{% include machine-command.html type='clickOnce' label='DEPOSIT 000001' machine='test1170' command='script' value='set Panel SR 000001;toggle Panel DEP' %}
+
+Step 15: Load ADDR register with 200:
+{% include machine-command.html type='clickOnce' label='LOAD 200' machine='test1170' command='script' value='set Panel SR 200;toggle Panel LOAD' %}
+
+Step 16: Set ENABLE and toggle START:
+{% include machine-command.html type='clickOnce' label='START' machine='test1170' command='script' value='set Panel ENABLE 1; toggle Panel START' %}
+
+Step 17: Load ADDR register with 300:
+{% include machine-command.html type='clickOnce' label='LOAD 300' machine='test1170' command='script' value='set Panel SR 300;toggle Panel LOAD' %}
+
+Step 18: Examine ADDR 300:
+{% include machine-command.html type='clickOnce' label='EXAM' machine='test1170' command='script' value='toggle Panel EXAM' %}
+
+Alternatively, with the PDPjs Debugger, the above "toggle-in" is easily entered with the following commands (the
+semicolons are optional; they just make it easier to paste an entire set of commands into the Debugger at once):
 
 	e 200 012737 000400 177572 012737 070707 000200 000000;
 	e 300 000300;
diff --git a/devices/pdp11/machine/1170/panel/debugger/xxdp/README.md b/devices/pdp11/machine/1170/panel/debugger/xxdp/README.md
index 1bb90c479..bb225b9a4 100644
--- a/devices/pdp11/machine/1170/panel/debugger/xxdp/README.md
+++ b/devices/pdp11/machine/1170/panel/debugger/xxdp/README.md
@@ -46,7 +46,8 @@ This machine is ready to boot [XXDP+ Diagnostics](/disks/dec/rl02k/xxdp/) ("BOOT
 
 We need to select a drive to load the [RL02K XXDP+ Diagnostics Disk](/disks/dec/rl02k/xxdp/), and since it is
 an RL02K disk, we need to use an RL02 drive.  A typical PDP-11 machine with a single [RL11 Disk Controller](/devices/pdp11/rl11/)
-could contain up to four such drives, which we refer to as RL0 through RL3.
+could contain up to four such drives, which we refer to as RL0 through RL3.  And since we want to boot the XXDP
+disk, we need to select drive RL0, since the boot code on the disk appears to assume drive 0. 
 
 To automatically boot the [RL02K XXDP+ Diagnostics Disk](/disks/dec/rl02k/xxdp/) and run the **EKBAD0** diagnostic,
 press: {% include machine-command.html type='button' label='Run EKBAD0' machine='test1170' command='runEKBAD0' %}
diff --git a/disks/dec/rl02k/xxdp/README.md b/disks/dec/rl02k/xxdp/README.md
index efe419b28..3e248a987 100644
--- a/disks/dec/rl02k/xxdp/README.md
+++ b/disks/dec/rl02k/xxdp/README.md
@@ -34,7 +34,8 @@ At the prompt, type "BOOT RL0".  The following text should appear:
 	
 	.
 
-NOTE: Any RL11 disk drive (RL0-RL3) can be used.  RL0 was selected for demonstration purposes.
+NOTE: In theory, any RL11 disk drive (RL0-RL3) could be used.  However, the boot code on the disk appears to assume
+drive 0, so RL0 should be selected.
 
 PDPjs has been tested with the following diagnostics:
 
diff --git a/docs/pcx86/examples/pcx86-dbg.js b/docs/pcx86/examples/pcx86-dbg.js
index 2e9a20964..64a66541b 100644
--- a/docs/pcx86/examples/pcx86-dbg.js
+++ b/docs/pcx86/examples/pcx86-dbg.js
@@ -68,7 +68,7 @@ function eb(a,b,c){gb[a]&&b&&(gb[a][b]=c)}function Wa(a){window&&window.alert(a)
 function lb(a,b){var c;if(void 0!==a){var d;b&&(b=0<(d=b.indexOf("."))?b.substr(0,d+1):"");for(d=0;d<bb.length;d++)if(c)c==bb[d]&&(c=null);else if(!(a!=bb[d].type||b&&bb[d].id.indexOf(b)))return bb[d]}return null}function mb(a){var b=null;if(a=a.getAttribute("data-value"))try{b=eval("("+a+")")}catch(c){Wa(c.message+" ("+a+")")}return b}function nb(a,b,c){var d;b&&(void 0===d&&(d="Panel"),(d=lb(d,a.id))&&(b=d.na[b])&&a.Cb(null,c,b))}
 function ob(a,b){b=pb(b.parentNode,"pcx86-control");for(var c=0;c<b.length;c++)for(var d=b[c].childNodes,e=0;e<d.length;e++){var f=d[e];if(1===f.nodeType){var g=f.getAttribute("class");if(g)for(var h=g.split(" "),k=0;k<h.length;k++)switch(g=h[k],g){case "pcx86-binding":(g=mb(f))&&g.binding&&a.Cb(g.type,g.binding,f,g.value),k=h.length}}}}
 function pb(a,b,c){c&&(b+="-"+c+"-object");if(a.getElementsByClassName)return a.getElementsByClassName(b);var d;c=[];a=a.getElementsByTagName("*");var e=new RegExp("(^| )"+b+"( |$)");b=0;for(d=a.length;b<d;b++)e.test(a[b].className)&&c.push(a[b]);return c}
-function qb(a,b,c){for(var d=!0;c<b.length;){var e=b[c],f=e[0],g=null;0<=sb.indexOf(f)&&(g=function(c){return function(){qb(a,b,c)}}(c+1));var h=tb[f];if(h)if(!g)d=h(e[1],e[2],e[3]);else{if(!h(g,e[1],e[2],e[3]))break}else{var d=!1,k=lb(e[1],a);if(k)if(h=ub[f])d=h(k,e[2],e[3]);else if(h=k.exports)if(h=h[f])if(d=!0,!g)d=h.call(k,e[2],e[3]);else if(!h.call(k,g,e[2],e[3]))break}if(!d){Wa("Script error ("+f+")");break}c++}return d}l=ab.prototype;
+function qb(a,b,c){for(var d=!0;c<b.length;){var e=b[c],f=e[0],g=null;0<=sb.indexOf(f)&&(g=function(c){return function(){qb(a,b,c)}}(c+1));var h=tb[f];if(h)if(!g)d=h(e[1],e[2],e[3]);else{if(!h(g,e[1],e[2],e[3]))break}else{var d=!1,k=lb(e[1],a);if(k)if(h=ub[f])d=h(k,e[2],e[3]);else{var m=k.exports;if(m&&(h=m[f]))if(d=!0,!g)d=h.call(k,e[2],e[3]);else if(!h.call(k,g,e[2],e[3]))break}}if(!d){Wa("Script error: "+f+(h?" failed":" unrecognized"));break}c++}return d}l=ab.prototype;
 l.toString=function(){return this.name?this.name:this.id||this.type};
 l.Cb=function(a,b,c){switch(b){case "clear":return this.na[b]||(this.na[b]=c,c.onclick=function(a){return function(){a.na.print&&(a.na.print.value="")}}(this)),!0;case "print":return this.na[b]||(this.Ie=this.na[b]=c,c.value="",this.P=function(a){return function(b,c){8192<a.value.length&&(a.value=a.value.substr(a.value.length-4096));a.value+=(void 0!==c?c+": ":"")+(b||"")+"\n";a.scrollTop=a.scrollHeight}}(c),this.Fa=function(a){this.P(a,this.be)}),!0;default:return!1}};l.log=function(){};l.P=function(){};
 l.status=function(a){this.P(this.be+": "+a)};l.Fa=function(a,b,c){c=c||this.type;b||Wa((c?c+": ":"")+a)};function vb(a,b){a.ea.error=!0;a.Fa(b)}function wb(a,b){b&&(a.ea.ready?b():a.pg=b);return a.ea.ready}function yb(a,b){a.ea.error||(a.ea.ready=!1!==b,a.ea.ready&&(b=a.pg,a.pg=null,b&&b()))}function zb(a,b){a.ea.pf&&(b?a.ea.$g=!0:void 0===b&&a.P(a.toString()+" busy"));return a.ea.pf}
diff --git a/docs/pcx86/examples/pcx86.js b/docs/pcx86/examples/pcx86.js
index 5e981791e..f62c6f243 100644
--- a/docs/pcx86/examples/pcx86.js
+++ b/docs/pcx86/examples/pcx86.js
@@ -66,7 +66,7 @@ function Pa(a){var b=!1;window&&(b=window.confirm(a));return b}function Qa(a){va
 function Sa(a,b){var c;if(void 0!==a){var d;b&&(b=0<(d=b.indexOf("."))?b.substr(0,d+1):"");for(d=0;d<Ma.length;d++)if(c)c==Ma[d]&&(c=null);else if(!(a!=Ma[d].type||b&&Ma[d].id.indexOf(b)))return Ma[d]}return null}function Ta(a){var b=null;if(a=a.getAttribute("data-value"))try{b=eval("("+a+")")}catch(c){r(c.message+" ("+a+")")}return b}function Ua(a,b,c){var d;b&&(void 0===d&&(d="Panel"),(d=Sa(d,a.id))&&(b=d.ia[b])&&a.wb(null,c,b))}
 function Va(a,b){b=Wa(b.parentNode,"pcx86-control");for(var c=0;c<b.length;c++)for(var d=b[c].childNodes,e=0;e<d.length;e++){var f=d[e];if(1===f.nodeType){var g=f.getAttribute("class");if(g)for(var h=g.split(" "),l=0;l<h.length;l++)switch(g=h[l],g){case "pcx86-binding":(g=Ta(f))&&g.binding&&a.wb(g.type,g.binding,f,g.value),l=h.length}}}}
 function Wa(a,b,c){c&&(b+="-"+c+"-object");if(a.getElementsByClassName)return a.getElementsByClassName(b);var d;c=[];a=a.getElementsByTagName("*");var e=new RegExp("(^| )"+b+"( |$)");b=0;for(d=a.length;b<d;b++)e.test(a[b].className)&&c.push(a[b]);return c}
-function Xa(a,b,c){for(var d=!0;c<b.length;){var e=b[c],f=e[0],g=null;0<=Ya.indexOf(f)&&(g=function(c){return function(){Xa(a,b,c)}}(c+1));var h=Za[f];if(h)if(!g)d=h(e[1],e[2],e[3]);else{if(!h(g,e[1],e[2],e[3]))break}else{var d=!1,l=Sa(e[1],a);if(l)if(h=ab[f])d=h(l,e[2],e[3]);else if(h=l.exports)if(h=h[f])if(d=!0,!g)d=h.call(l,e[2],e[3]);else if(!h.call(l,g,e[2],e[3]))break}if(!d){r("Script error ("+f+")");break}c++}return d}k=t.prototype;
+function Xa(a,b,c){for(var d=!0;c<b.length;){var e=b[c],f=e[0],g=null;0<=Ya.indexOf(f)&&(g=function(c){return function(){Xa(a,b,c)}}(c+1));var h=Za[f];if(h)if(!g)d=h(e[1],e[2],e[3]);else{if(!h(g,e[1],e[2],e[3]))break}else{var d=!1,l=Sa(e[1],a);if(l)if(h=ab[f])d=h(l,e[2],e[3]);else{var m=l.exports;if(m&&(h=m[f]))if(d=!0,!g)d=h.call(l,e[2],e[3]);else if(!h.call(l,g,e[2],e[3]))break}}if(!d){r("Script error: "+f+(h?" failed":" unrecognized"));break}c++}return d}k=t.prototype;
 k.toString=function(){return this.name?this.name:this.id||this.type};
 k.wb=function(a,b,c){switch(b){case "clear":return this.ia[b]||(this.ia[b]=c,c.onclick=function(a){return function(){a.ia.print&&(a.ia.print.value="")}}(this)),!0;case "print":return this.ia[b]||(this.Cf=this.ia[b]=c,c.value="",this.lc=function(a){return function(b,c){8192<a.value.length&&(a.value=a.value.substr(a.value.length-4096));a.value+=(void 0!==c?c+": ":"")+(b||"")+"\n";a.scrollTop=a.scrollHeight}}(c),this.Aa=function(a){this.lc(a,this.Td)}),!0;default:return!1}};k.log=function(){};k.lc=function(){};
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diff --git a/modules/markout/lib/markout.js b/modules/markout/lib/markout.js
index 3f0e1d183..3dc8b201a 100644
--- a/modules/markout/lib/markout.js
+++ b/modules/markout/lib/markout.js
@@ -1301,7 +1301,13 @@ MarkOut.prototype.convertMDMachineLinks = function(sBlock)
         if (!aParms) continue;
         sReplacement = "";
         sMachineID = findParm(aParms, 'machine');
-        var sControl = findParm(aParms, 'type') || 'button';
+        var sSingle = "false,";
+        var sControl = findParm(aParms, 'type');
+        if (sControl == "clickOnce") {
+            sControl = "";
+            sSingle = "true,";
+        }
+        sControl = sControl || "button";
         var sControlType = sControl == 'button'? ' type="button"' : '';
         if (this.aMachineDefs[sMachineID]) {
             var sCommand = findParm(aParms, 'command');
@@ -1312,7 +1318,7 @@ MarkOut.prototype.convertMDMachineLinks = function(sBlock)
             } else if (sValue) {
                 sValue = sValue.replace(/"/g, "&quot;");
             }
-            sReplacement = '<' + sControl + sControlType + ' onclick="commandMachine(';
+            sReplacement = '<' + sControl + sControlType + ' onclick="commandMachine(this,' + sSingle;
             sReplacement += "'" + sMachineID + "',";
             sReplacement += "'" + findParm(aParms, 'component') + "',";
             sReplacement += "'" + sCommand + "',";
diff --git a/modules/pdp11/lib/panel.js b/modules/pdp11/lib/panel.js
index ebdb9eabf..56ebe9539 100644
--- a/modules/pdp11/lib/panel.js
+++ b/modules/pdp11/lib/panel.js
@@ -162,7 +162,7 @@ class PanelPDP11 extends Component {
             'TEST':     [0, 0, true,  false, this.processLEDTest]
         };
         for (var i = 0; i < 22; i++) {
-            this.switches['S'+i] = [0, 0, false, false, this.processSwitchReg, i];
+            this.switches['S'+i] = [0, 0, false, false, this.processSRSwitch, i];
         }
 
         /** @type {ComputerPDP11} */
@@ -179,14 +179,23 @@ class PanelPDP11 extends Component {
 
         /*
          * The 'hold' and 'toggle' exports, which map to holdSwitch() and toggleSwitch(), both press and release
-         * the specified switch, but processCommands() considers a 'hold' function to be asynchronous, which means it
-         * will be passed a callback function that can be used to implement a delay.  toggleSwitch() doesn't support
-         * a delay, so it should only be used with toggles (eg, 'ENABLE'), not momentary switches (eg, 'TEST').
+         * the specified switch, but processCommands() considers a 'hold' function to be asynchronous, which means
+         * that holdSwitch() will be passed a callback function that can be used to implement a delay between the
+         * press and the release, whereas toggleSwitch() will not.
+         *
+         * holdSwitch() only makes sense for momentary switches (eg, 'TEST'), where a visual delay might be nice.
+         * If the switch isn't momentary, or no delay is desired, then use toggleSwitch(); it will be more efficient.
+         *
+         * Finally, for switches that are toggles (eg, 'ENABLE'), you can use setSwitch() to set it to a specific
+         * state: zero for "off" and non-zero for "on".  setSwitch() also supports meta-switches like "SR", using
+         * the entire value to set a series of switches at once; the value is assumed to be octal unless overridden
+         * by a prefix (eg, "0x") or suffix (eg, ".").
          */
         this['exports'] = {
             'hold': this.holdSwitch,
             'toggle': this.toggleSwitch,
-            'reset': this.resetSwitches
+            'reset': this.resetSwitches,
+            'set': this.setSwitch
         };
 
         this.setReady();
@@ -255,7 +264,7 @@ class PanelPDP11 extends Component {
      */
     setSR(value)
     {
-        this.setSwitches(value);
+        this.setSRSwitches(value);
     }
 
     /**
@@ -631,6 +640,28 @@ class PanelPDP11 extends Component {
         return true;
     }
 
+    /**
+     * setSwitch(sBinding, sValue)
+     *
+     * @this {PanelPDP11}
+     * @param {string} sBinding
+     * @param {string} sValue
+     * @return {boolean}
+     */
+    setSwitch(sBinding, sValue)
+    {
+        if (sBinding == "SR") {
+            return this.setSRSwitches(Str.parseInt(sValue, 8))
+        }
+        var sw = this.switches[sBinding];
+        if (sw) {
+            sw[1] = +sValue? 1 : 0;
+            this.displaySwitch(sBinding, sw[1]);
+            return true;
+        }
+        return false;
+    }
+
     /**
      * toggleSwitch(sBinding)
      *
@@ -736,12 +767,16 @@ class PanelPDP11 extends Component {
     processStart(value, index)
     {
         if (!value && !this.cpu.isRunning()) {
+
+            this.cpu.setPC(this.regAddr);
+
             /*
              * TODO: Verify what the PDP-11/70 Handbook means when it says that when the 'START' switch
              * is depressed, "the computer system will be cleared."  I take it to mean that it performs
              * the equivalent of a RESET instruction.
              */
             this.cpu.resetCPU();
+
             /*
              * The PDP-11/70 Handbook goes on to say: "If the system needs to be initialized but execution
              * is not wanted, the START switch should be depressed while the HALT/ENABLE switch is in the HALT
@@ -955,18 +990,18 @@ class PanelPDP11 extends Component {
             /*
              * This is another one of my "innovations": when you're done testing the LEDs, all the switches reset as well.
              */
-            this.setSwitches(0);
+            this.setSRSwitches(0);
         }
     }
 
     /**
-     * processSwitchReg(value, index)
+     * processSRSwitch(value, index)
      *
      * @this {PanelPDP11}
      * @param {number} value (normally 0 or 1, but we only depend on it being zero or non-zero)
      * @param {number} index
      */
-    processSwitchReg(value, index)
+    processSRSwitch(value, index)
     {
         if (value) {
             this.regSwitches |= 1 << index;
@@ -1066,31 +1101,37 @@ class PanelPDP11 extends Component {
     }
 
     /**
-     * hasSwitches(value)
+     * hasSRSwitches(value)
      *
      * @this {PanelPDP11}
      * @return {boolean}
      */
-    hasSwitches()
+    hasSRSwitches()
     {
         return this.bindings[PanelPDP11.SWITCH.S0] !== undefined;
     }
 
     /**
-     * setSwitches(value)
+     * setSRSwitches(value)
      *
      * @this {PanelPDP11}
-     * @param {number} value
+     * @param {number|undefined} value
+     * @return {boolean}
      */
-    setSwitches(value)
+    setSRSwitches(value)
     {
-        if (this.hasSwitches()) {
-            this.regSwitches = value;
+        if (this.hasSRSwitches() && !isNaN(value)) {
+            this.regSwitches = value | 0;
             for (var i = 0; i < 22; i++) {
-                this.switches['S'+i][1] = (value & (1 << i))? 1 : 0;
+                this.switches['S'+i][1] = (this.regSwitches & (1 << i))? 1 : 0;
             }
+            /*
+             * This (re)displays ALL switches, not merely the SR switches, but that's OK.
+             */
             this.displaySwitches();
+            return true;
         }
+        return false;
     }
 
     /**
diff --git a/modules/shared/lib/component.js b/modules/shared/lib/component.js
index 7af064d2c..381132d81 100644
--- a/modules/shared/lib/component.js
+++ b/modules/shared/lib/component.js
@@ -621,11 +621,19 @@ class Component {
     /**
      * Component.getScriptCommands(sScript)
      *
-     * Backslash sequences like \n, \r, and \\ have already been converted to LF, CR and backslash
-     * characters, since the entire script string was injected into a JavaScript function call, so
-     * any backslash sequence that JavaScript supports was automatically converted.
+     * This is a simple parser that breaks sScript into an array of commands, where each command
+     * is an array of tokens, where tokens are sequences of characters separated by any of: tab, space,
+     * carriage-return (CR), line-feed (LF), semicolon, single-quote, or double-quote;  if a quote is
+     * used, all characters up to the next matching quote become part of the token, allowing any of the
+     * other separators to be part of the token.  CR, LF and semicolon also serve to terminate a command,
+     * with semicolon being preferred, because it's 1) more visible, and 2) essential when the entire
+     * script is a multi-line string where all CR/LF were replaced by spaces (which is what Jekyll does,
+     * and since we can't change Jekyll, it's what our own MarkDown Front Matter parser does as well;
+     * see convertMD() in markout.js, where the aCommandDefs array is built).
      *
-     * The complete list of backslash sequences supported by JavaScript:
+     * Backslash sequences like \n, \r, and \\ have already been converted to LF, CR and backslash
+     * characters, since the entire script string is injected into a JavaScript function call, so any
+     * backslash sequence that JavaScript supports is automatically converted:
      *
      *      \0  \'  \"  \\  \n  \r  \v  \t  \b  \f  \uXXXX \xXX
      *                      ^J  ^M  ^K  ^I  ^H  ^L
@@ -717,11 +725,21 @@ class Component {
     static processCommands(idMachine, aaCommands, iCommand)
     {
         var fSuccess = true;
+
+     // var dbg = Component.getComponentByType("Debugger", idMachine);
+
         while (iCommand < aaCommands.length) {
 
             var aTokens = aaCommands[iCommand];
             var sCommand = aTokens[0];
 
+            /*
+             * It's possible to route this output to the Debugger window with dbg.println()
+             * instead, but it's a bit too confusing mingling script output in a window that
+             * already mingles Debugger and machine output.
+             */
+            Component.println('script: ' + aTokens.join(' '));
+
             var fnCallReady = null;
             if (Component.asyncCommands.indexOf(sCommand) >= 0) {
                 fnCallReady = function processNextCommand(iNextCommand) {
@@ -731,26 +749,26 @@ class Component {
                 }(iCommand + 1);
             }
 
-            var fnScript = Component.globalCommands[sCommand];
-            if (fnScript) {
+            var fnCommand = Component.globalCommands[sCommand];
+            if (fnCommand) {
                 if (!fnCallReady) {
-                    fSuccess = fnScript(aTokens[1], aTokens[2], aTokens[3]);
+                    fSuccess = fnCommand(aTokens[1], aTokens[2], aTokens[3]);
                 } else {
-                    if (!fnScript(fnCallReady, aTokens[1], aTokens[2], aTokens[3])) break;
+                    if (!fnCommand(fnCallReady, aTokens[1], aTokens[2], aTokens[3])) break;
                 }
             }
             else {
                 fSuccess = false;
                 var component = Component.getComponentByType(aTokens[1], idMachine);
                 if (component) {
-                    fnScript = Component.componentCommands[sCommand];
-                    if (fnScript) {
-                        fSuccess = fnScript(component, aTokens[2], aTokens[3]);
+                    fnCommand = Component.componentCommands[sCommand];
+                    if (fnCommand) {
+                        fSuccess = fnCommand(component, aTokens[2], aTokens[3]);
                     }
                     else {
                         var exports = component['exports'];
                         if (exports) {
-                            var fnCommand = exports[sCommand];
+                            fnCommand = exports[sCommand];
                             if (fnCommand) {
                                 fSuccess = true;
                                 if (!fnCallReady) {
@@ -765,7 +783,7 @@ class Component {
             }
 
             if (!fSuccess) {
-                Component.alertUser("Script error (" + sCommand + ")");
+                Component.alertUser("Script error: " + sCommand + (fnCommand? " failed" : " unrecognized"));
                 break;
             }
 
diff --git a/modules/shared/lib/sticky.js b/modules/shared/lib/sticky.js
index afc0da659..4ac914747 100644
--- a/modules/shared/lib/sticky.js
+++ b/modules/shared/lib/sticky.js
@@ -88,7 +88,7 @@ function addStickyMachine(idMachine, sPosition)
 }
 
 /**
- * commandMachine(idMachine, sComponent, sCommand, sValue)
+ * commandMachine(control, fSingle, idMachine, sComponent, sCommand, sValue)
  *
  * Note that this script is not compiled into any of the machines, since "sticky machines" are feature of the PCjs
  * website rather than of the machines.  And since the machines are compiled, all their code and data is completely
@@ -103,14 +103,19 @@ function addStickyMachine(idMachine, sPosition)
  * component is found, then its 'exports' table is checked for an entry matching the specified command string, and if
  * an entry is found, then the corresponding function is called with the specified data.
  *
+ * @param {Object} control
+ * @param {boolean} fSingle
  * @param {string} idMachine
  * @param {string} sComponent
  * @param {string} sCommand
  * @param {string} [sValue]
  * @return {boolean}
  */
-function commandMachine(idMachine, sComponent, sCommand, sValue)
+function commandMachine(control, fSingle, idMachine, sComponent, sCommand, sValue)
 {
+    if (fSingle) {
+        control.disabled = true;
+    }
     if (sCommand == "script" && window.processMachineScript) {
         return window.processMachineScript(idMachine, sComponent, sValue);
     }