For the playfield lights issue, check the following:
10 amp fuse and fuse holder - white wire and white/red wire
H relay switch - white/red wire and white/black wire
Playfield Jones Plugs - unplug, make sure plugs are clean, re-seat the plugs
For the restarting issue:
We'll need to look at all the possible ways power can get to the start relay (S relay).
When a game is in progress, power comes from the transformer and sends power through a series of normally closed (NC) switches to the following normally open (NO) switches:
Replay button switch - brown wire and orange wire
#1 coin chute switch - orange wire and blue wire
#2 coin chute switch - orange wire and yellow wire (if installed)
#3 coin chute switch - orange wire and green wire (if installed)
The three coin switches are armed and ready to send power toward the start relay. The replay button switch is armed and ready if there are credits showing on the credit wheel. If any of these switches close during a game, the game will reset. Questions: When the machine has zero credits during game play, does the restart problem happen? Is the machine set for coin play or free play?
Another way power can get to the start relay during a game, is through the following switches that are normally open (NO):
W relay switch - slate wire and orange/white
S relay switch - slate wire and orange/white
If these switches are out of adjustment or have a short, they can cause the machine to restart during a game.
Another test: With the coin door Jones plugs connected, play a game with the coin door swung open. Does the machine reset by itself during a game when the coin door is open?
Vibration issues: Are any of the coin switches or replay button gapped too closely? Switches that are gapped too closely could cause the machine to reset during a game...