Well, they let this in https://www.wincustomize.com/skins.asp?authorid=665624

Not to mention a few others.
That didn't take any expensive 3d software, could do it in MS Paint
Wonder which admin approved that? If it was a group approval, I'm speechless. Somebody is a little trigger happy on the approve button or just impatient.
Oh well at least your skin won't be rejected(as long as you use your own graphics).