CODE TO GO ON THE MAIN TIMELINE:


stop();

addEventListener("NEXT", next);
function next(e:Event):void{
  nextFrame();
}

CODE TO GO INSIDE THE MOVIE CLIP, ON THE ACTIONS LAYER:

stop();

bomb_btn.addEventListener(MouseEvent.MOUSE_DOWN, mouseDownHandler1);
function mouseDownHandler1(e:Event):void{
  dispatchEvent(new Event("NEXT", true));
}