I got 12k, how do you get so many points?
If you can light all 3 targets at the top of the screen, your multiplier will increase. This means all points scored are doubled, tripled, etc.
If you get one target lit, you can move it's position by pressing the flipper (i.e. pressing Left/Right).
That means if you can get the ball to bounce through even a single slot a few times, you can still increase your multiplier with smart movement of the targets.