I saw that there was many attemps to create a wheel creature. So I tried for myself and here's the fuit of my work!
It took several hundreds of start before having something decent to let it evolve lol.
The creature didn't seems to be able to understand that it's top and bottom can be any bone/joint. My idea was that the creature could somehow understand that it can always put its inner wheel to face foward, whatever its position, and so making the wheel accelerate indefinitely to the point where the ratio gravity/speed will reach it's top.