flash actionscript: Is it possible to control a movie clip from a button which is part of another
movie clip?

For example:

If I wanted movie clip X to goto frame 5 and play when a button in movie clip
Y is pressed. Leaving both movie clip Y timeline and the main timeline static.

Yes, as long as you scope everything properly, there should be no problem. So,
something like this code should be placed on the main timeline (you could put
it elsewhere as well, but for the sake of simplicity):

mcY.mcYbutton.onRelease = function(){

mcX.gotoAndPlay(5);

}


Hope that helps!
/david