Just thought I would add.... it was quite astute of you to notice the flipper behavior. What happened here exactly is your 12 Volt voltage dropped as you noted. This affects the flipper optos so that they send a very rapid on/off repeated pulse to the fliptronics which leads to bad things. Instead of a flipper coil switching from high power coil to low power when the flipper is held, to rapidly pulsing the high power coil only. So rapid in fact, its the same as keeping the high coil constantly energized. This gets the coil very hot in a hurry. If you would have felt it, it would have been extremely hot. When coils get this hot, their power is reduced. Not sure why, but they do. Much more of that and you would have blown the fuse, melted the coil, or a combination of the 2. You're probably ok, but might want to check coil resistance just to be safe. Good luck. Sounds like you are on your way to getting the 12V issure figured out....

-Jeff