LoadMovie, control from maintimeline to external swf AS?

I have an external swf that I’ve placed in an empty movie clip using loadmovie into the main movie.

The swf shows and plays fine, however I have an interactive movie clip which does nothing when loaded into the main movie. (note: the loaded .swf is fine when tested outside of the main movie). How do I target the external .swfs interactive features after it has been loaded into the main timeline?

here’s an example:

code in the external .swf-- on a movieclip, instance name: growObject

onClipEvent (enterFrame) {
if (_root.grow == 1 && this._xscale<300) {
this._xscale += 20;
}
if (_root.grow == 0 && this._xscale>73) {
this._xscale -= 20;
}
}

code on a button (which controls the above code and is also located in the external swf–

on(rollOver){
grow=1;
}
on(rollOut){
grow=0;
}

I just need to figure out how to activate these instances while watching the external swf from my main movie timeline. I am LOST.

Thanks for any input, examples, tutorial references!!! :jail: