Oh, I see. Internally inconsistent.
I've had one that works on every PC I've run it on except my PC at home, where it doesn't work, and I've had one that if you click Back, then stop and restart it (without exiting and reloading) it doesn't work the second time.
Otherwise they've been consistent in their misbehavior.
I wonder if the installed Flash version has anything to do with it? I haven't actually tried updating the one at home. . . . .
And as for adding something and making it work or not work, if you make a small change to a normal contraption, if it fails afterwards it fails by a small amount, a little bit off on the timing, or the toss is short, whatever. You can see what's wrong and adjust. Changing a bomb device changes EVERYTHING. The bomb gets weaker or stronger, goes off at a different time or a different direction, subsequent booms time differently as well. There is absolutely no way of predicting the outcome.
(But the outcome should be the same every time you run it.)