I cannot reproduce that.
Can you try again?
If the debugger shows, what is the return value of "this.getOperation(false)"?
If that is undefined, can you try to step into this.getOperation(false) and see where it fails?

.eval this.getOperation(false)==undefined

Rotate.prototype.getOperation = function(preview) {
    if (!isValidVector(this.centerPoint)) {
=>        return undefined;
    }
...

qsdb> this.centerPoint == undefined
true

Committed potential fix. The tool might not do anything anymore though, if this.centerPoint is NULL.

nope, still the same

similar problem with scale:

Uncaught exception at scripts/Modify/Scale/Scale.js:123: Error: :-1:-1: Wrong number/types of arguments for RDocumentInterface.applyOperation().
<native>(undefined) at -1
<anonymous>(event = RCoordinateEvent(0xbfffd478), preview = false) at scripts/Modify/Scale/Scale.js:123
<anonymous>(event = RCoordinateEvent(0xbfffd478)) at /home/martin/workspace/rsframework/scripts/Modify/../EAction.js:1197
<global>() at -1
123	                di.applyOperation(op);

Scale.prototype.getOperation = function(preview) {
    if (!isValidVector(this.focusPoint)) {
=>        return undefined;
    }

I still cannot reproduce this here.

I've added some debugging output to Rotate.js. Can you pls post the output here? Thx.

Edit: I've also added some fail safe code, it might not show the same symptoms anymore.

doesn't crash anymore, but does nothing now

Debug:    updateScenes... 
Debug:    updateGuiActions... 
Debug:    notifyListenersSlot... 
Debug:    setActiveSubwindow... 
Warning:  QScriptEngine::newVariant(): changing class of non-QScriptObject not supported
Warning:  RScriptHandlerEcma::createActionDocumentLevel():  "scripts/Snap/Auto/Auto.js" : Engine is busy. Aborting... 
Warning:  RScriptHandlerEcma::createActionDocumentLevel():  "scripts/Snap/RestrictOff/RestrictOff.js" : Engine is busy. Aborting... 
Debug:    Rotate.setState: setting this.centerPoint to undefined 
Debug:    Rotate.pickCoordinate: setting this.centerPoint to  RVector(12, 16, 0)  
Debug:    updateScenes... 
Debug:    updateGuiActions... 
Debug:    notifyListenersSlot... 
Warning:  RScriptHandlerEcma::createActionDocumentLevel():  "scripts/Snap/Auto/Auto.js" : Engine is busy. Aborting... 
Warning:  RScriptHandlerEcma::createActionDocumentLevel():  "scripts/Snap/RestrictOff/RestrictOff.js" : Engine is busy. Aborting... 
Debug:    setActiveSubwindow... 
Debug:    Rotate.setState: setting this.centerPoint to undefined 
Debug:    Rotate.getOperation: failed, this.centerPoint is not valid 
Debug:    updateScenes... 
Debug:    updateGuiActions... 
Debug:    notifyListenersSlot... 
Debug:    setActiveSubwindow... 
Debug:    Rotate.setState: setting this.centerPoint to undefined 
Debug:    updateScenes... 
Debug:    updateGuiActions... 
Debug:    notifyListenersSlot... 
Warning:  QScriptEngine::newVariant(): changing class of non-QScriptObject not supported
Warning:  QScriptEngine::newVariant(): changing class of non-QScriptObject not supported
Debug:    setActiveSubwindow... 

Thanks. I can reproduce it now. Looks like under Linux there's a focus change when the dialog opens. I can simulate that by switching applications. Will try to fix.

rotate should be fixed now, please confirm, then I'll fix scale

yes, the dialog is surrounded with a blue border, means it has he focus (the focus taken away from the main window)

rotate is OK now

OK, updated scale as well.