That's VPX physics & collisions, I don't think there is much to do. You can change a little the walls which touches the ball, but sooner or later it will start doing that again.
This is perhaps not perfect but ball does not move

I have a different question though
When game is over, top slighshots are active, also when tilted top slingshots are active (in the sword arena)
And when during normal play, i can nudge the ball and set the arena in motion, and can literally then just sit there racking up a score with the ball sitting in the shooter lane.
I do not know, is that possible on the real table?
If not, perhaps adding a solenoid check to see if those slingshot solenoids are enabled would take care of it?
If you feel the need to empty your wallet in my direction, i don't have any way to receive it anyways
Spend it on Hookers and Blow