is it an opto problem?
do all optos have 12v going to them?
cant remember if the ball trough on these have optos but if they do you might have a bad connection on the opto transmit board or a bad solder joint.
I have only speed read through this post so sorry if i am leading you up the path. i dont have much time to read any thing properly lately as i am snowed under in board repairs 
The right through switch is an Opto . As this is my 1st DMD and my next newest game is Firepower, all this stuff is new to me .
I will check if the Opto has power .
Thanks Beaky
