As a fellow monkey ball submitter, i'd be really interested in seeing how you handled the rotation logic. ours was rotating the map around 0,0 using the linear velocity vector to kind of orient the rotation, but we found that the further from 0,0 you go, the more jarring the rotations could be, so we needed to use a damping factor the further from 0,0. this looks much smoother :P
I'll definitely check yours out! We actually had a couple of different thoughts on it. First we tried just manipulating the gravity vector, and although that works, any other rigidbodies in the world fall incorrectly. The 2nd thing we did was to set the pivot point of the entire level, and all the objects to the location of the character. The tilt the level on the x or z axis based on that pivot point. The source code is actually published if you want to take a look here:
https://github.com/enmae/20-Games-Challenge-Jam-2025/blob/68ee8084e730bfa751cd1d...