1. If you are losing half of the pf lights during play you may have a cold solder connection for the respective pins on the board. You might also try replacing the fuse and/or making sure you have a good connection at the fuse holder. Try disconnecting and reconnecting molex on power board.
2. Does the slot machine eject work in solenoid test? Repeat steps in #1. Make sure wires are intact on eject mechanism.