Devi settare la larghezza a caricamento completato:

codice:
var mc = this.createEmptyMovieClip(struct[x].name, this.availableDepth++);
mc._x = struct[x].left;
mc._y = struct[x].top;
mc.createEmptyMovieClip("loader", 1);
mc.loader._alpha = 0;
mc.loader.loadMovie("jazz.jpg");
mc.onEnterFrame = function()
{
	var car = this.loader.getBytesLoaded();
	var tot = this.loader.getBytesTotal();
	if(car >= tot && tot > 4){
		this.onEnterFrame = undefined;
		this.loader._width = 200;
		this.loader._alpha = 100;
	}
}