Rochester, NY
Try just disabling the claw and see if it makes a difference. Also make sure your coin door is closed? I had tons of problems getting mine working where sometimes it would just refuse to start a game, and I also had some claw opto issues. After replacing claw optos and lots of other work I also haven't had the starting issue anymore. I think the claw should be at the far left; make sure it is, and that the claw optos are reading correctly there.
I'm not familiar with the great lakes opto board, but in switch test with all balls loaded, the jam switch should read the opposite of the other trough switches
