Nice demo ventilator. I couldn't get the ball to fall through the level after trying for a couple minutes. It is a trivial issue if it takes a lot of work to make it mess up.

I was thinking of trying to use trace as a method to limit the problems I had earlier. I hadn't quite thought of how I wanted to approach it though. I like your movement through torque as well.

I'm not sure of how to limit that odd spin reaction either. Can you think of something that would reduce/eliminate that? Or why that might occur at all?

thanks,
Jason