The submission has the things you suggested, including caching the RegularPolygon colliders and creating clones. The only task I couldn't complete before submission was limiting the number of active sound entities.
We conducted tests using ball colliders, and it turns out that more colliders can be active this way. Interestingly, xpbd seems to encounter limitations when dealing with a large number of constructed colliders.
I also updated collision events to utilize radial distance checks for game logic tasks like combining shapes, instead of relying on xpbd collision events, which provide precise polygon collision detection. Unfortunately, there was a mistake in the code for collision checks in the published version. Objects were colliding and combining when they shouldn't have been. This happened due to accidentally shadowing a variable in one of the closures, causing the wrong transform to be used.
