I can sort of see this sphere rolling problem - I just tried driving the car slowly forward in SRX and although it gently rolls along and comes to a gradual halt, it's not perfect - there is still slight creep if the car sits still - it will very very slowly slide to one side, which I assume is because of this sphere problem you mention. I have reduced it by making a variable friction and damping system that increases certain values as the vehicle slows, allowing it to stop, but the creep is still present if you leave it long enough - no idea how to get rid of that, short of resetting the car's position if it isn't moving.
Still, SRX isn't about sitting still in one place, so I don't really care in this context, but it is still not too good though that a rigid body can't sit stationary on another...
Still, SRX isn't about sitting still in one place, so I don't really care in this context, but it is still not too good though that a rigid body can't sit stationary on another...