I am working on a Pinbot too. If the switch contacts are worn just replace the switch. Pretty easy to do and not expensive. I rebuilt my flippers and replaced the lane change switches while I was at it.

I replaced all the light bulbs in the matrix with LED's. I used the Ablaze LED's and got them from Pinballlife.com these LED's work great. Did the matrix lights work when you had light bulbs installed? If they did then the problem is most likely with the LED's and not something else.

Hope this is helpful.

Al