ezeltmann:
looks closely at the socketed chip on your CPU board. maybe CAREFULLY pop it out with a flatblade screwdriver and reseat it making sure all pins are seated and none are bent over or hanging out of the socket.
Seen it before on several Sterns.
When Dip #8 is on, the machine is booting from this chip. of it's not seated correctly or the chip has a programming error, you'll get no display and machine will appear dead.

file size is under 80MB. I think it's more of how the USB device is formatted. FAT32 is probably the best bet.
I've used up to 32GB drives to update and all work fine.

** update did not fix the left outlane.

lol Man that thing is huge!

not a fan of warm white LEDs myself, but I have to admit, that looks really nice.
Perhaps the colors used on this game would look better with warm.