Quoted from dgpinball:I'm not really good at diagnosing problems like this without my hands on the machine, but Problem 1 sounds like it could be jones plug related, or if you have a schematic, check for a relay switch that might cut the power to the playfield lamp section, and of course check the blades on the tilt relay.
Problem 2 I would look at the 1 point relay, make sure all the blades are making good contact and are clean, and then the contacts on the score motor that pulses that relay to give you the 5 points.
I agree, sounds like a jones plug issue.
Also in response to your question on the tilt relay - there are several blades - one set will control the lights.