while turning back my megaminx Earth the cube got scrambled and I didn't realize why. So I tried to fix the messed up part of the cube, only to see that my light yellow 0-face was turning now as a 1-face most of the time (not allways).

Should I look for the center part and sand it more round? Turning the screw had not much effect....

Thanks for helping,
Michael

A 0 centre piece has to be stationary, right?
The pentagon connects to the core and the screw has to be tightened enough to avoid rotation.
I have not disassembled my Earth any further to take this picture, but when I reassembled it and had not tightened the screw, the circle turned.

I do not see how sanding the centre piece can help. Have you tried to get the screw really tight?
I have used the opportunity to get some training, before my Uranus arrives which is complementing my Earth to make any of the planets.

Thanks for the answer. I have seen the images of the parts of a crazy megaminx here and don't want to puzzle it like this way

I took will try to screw the center more tightly, I don't wnat to break something. If that face now allways turns like a 1-face, well than I have a new planet
But I like my Earth...

cheers,
Michael