Simple to use. Just remix and put in your own "When I Receive [When Stop Clicked]" script. Also, make sure you click the "set tt to 0" block in the Stage before sharing! Annoy people with this :P Or make a cloud-related thing, whatever your heart desires :P
Finally! A way to make a When Stop Clicked block! Using the Timer and the When block, which run even when the program is stopped, I made a stop event.