Why on earth would you want to use mudbox? Can it even display textures?
Besides, you can't post a sculpt as your submission, in fact, you're not allowed to change the lowpoly model at all other than it's uv's. You're allowed to do a highpoly one, yes. But you can't use the highpoly in your submission, it's only to bake textures from.
I'd suggest you get a realtime shader or a game-engine
