Ball between flippers can sometimes come back from the middle pop bumper. Skillful nudging may help.
Shake machine back and forth to save ball from center pop
1-6 add value to center hole (up to 6k), but all 6 light loop for special which resets 1-6, be careful!
Center shot is usually repeatable if you can control the ball. Try bounce passing off right flipper from kickout.
Loop is worth 5k all the time, no need to build up like kickout, but more dangerous. Give good horizontal nudge as ball comes down to pop