First, a million thanks to the wonderful people in these forums who have helped me get as far as I have (especially DaveC whose sample 'pizza' game helped me nail down the random spawn structure in general).
I have the bare-bones structure of a game, fairly simple - the goal for the part I'm working on specifically is that there's a countdown timer from 30 to 0, and when it hits 0, it spawns a new enemy at a random point at the bottom of the screen (oh, and a randomized enemy at that, because I'm a glutton for punishment). I managed to get it correctly set up to randomize the enemy and spawn point. The counter is set to start at 30 and reduce by one every second, and when it hits zero, it resets to 30 and starts again. The goal is that the reset to 30 is also the trigger for the enemy to spawn, and I have that part working... except that it spawns several enemies at once instead of only one. If I change it so the event is based on the game timer (to spawn an enemy every thirty seconds), it works just fine, but when it's based on the counter showing 30, it spawns multiple enemies at once - something like 2-3 dozen??? It's insane.
Any ideas on what's going wrong here? Any suggestions on how to fix it?
(I've attached my work so far in case anyone wants to check it out.)