The developing of this game took only two days. It has 280 lines of code. And I still didn't finish the work with a timer. I need to add the "Pause" button as well. The main problem was the lack of knowledge about .mouseChildren command (It works with events propagation).
puzzle.mouseEnabled = true;
puzzle.addEventListener(MouseEvent.MOUSE_DOWN, onDrag);
puzzle.addEventListener(MouseEvent.MOUSE_UP, onDrop);
puzzle.mouseChildren = false;
This application has 348 Kb size and uses 89% of CPU when you play a prize Game due to having 48 interactive animations.