I don't know if my analysis of this glitch is correct, but as far as I can tell this is the only explanation.
I have a game, where there is a global variable "Number of dead enemies." Every time an enemy is killed, it adds one to this variable. When this variable reaches 24, the game should display a win game screen. However, on random browsers, and at random times(I have tested this on Firefox, it happened the first time and didn't happen the second), the variable appears not to register, and the End Game layout does not appear.
The only other thing about this glitch I have noticed, is that at the start of the layout, instead of waiting 5 seconds like I programmed them, the enemy spawners create the enemies as soon as the layout loads. This always corresponds to the "No End Game" glitch.
Link to Capx: docs.google.com/file/d/0Bz5x2REX7ZtRMlRjUDVoLWVaZEU/edit
Sorry its sort of messy.