Non mi pare che c'entri molto l'oggetto Selection. Invece del rollover e rollout, usa l'hitTest:

codice:
areaSensibileUp.sopra = false;
areaSensibileUp.onMouseMove = function()
{
	if(this.hitTest(_root._xmouse, _root._ymouse, true)){
		if(!this.sopra){
			this.sopra = true;
			this.rollingOver();
		}
	} else {
		if(this.sopra){
			this.sopra = false;
			this.rollingOut();
		}
	}
};

areaSensibileUp.rollingOver = function()
{
	trace("up")
	baseContainer.McTrascina._visible=1
	baseContainer.McScale._visible=1
	areaSensibileUp.swapDepths(baseContainer)
}

areaSensibileUp.rollingOut = function()
{
	trace("down")
	baseContainer.McTrascina._visible=0
	baseContainer.McScale._visible=0
	baseContainer.swapDepths(areaSensibileUp)
}