I'm guessing there is a simple explanation for this. Any tips would be gratefully appreciated.

Upon further review... the Q relay is remaining energized.

I did. It's a make switch that is closed when Q is energized. I must be getting something wrong.

I guess something is keeping Q energized (when it's plugged in and on) when it shouldn't be.

I understand that it's supposed to be closed when the power is off. I'll recheck the relay.

OK. I carefully checked the relay. The switch is a break switch, so when energized it is not closed, just like the schematic indicates. The Q relay fires, the switch (with the red+white wire) opens and... the flippers are still energized. I actually placed a non conductive strip in the switch and checked for a short at or near the switch. Thanks to you and several other forum members I'm starting to parse schematics, but I seem to be missing something on this one.

I think the challenge is that the Q switch is open at the end of the game and the flippers are still energized. Here's a question: After I turn on the power, but before I press start, both the game over (Q) and 1st ball (U) relays are energized. Does that sound right?