Quick bonecrusher questions

How are his legs, or feet rather, supposed to be transformed? It seems to have movement down there, but in seibs gallery and maybe the instructions it doesn't look like you need to do anything really. I put one set of wheels completely under his leg as opposed to being on the side.
My second question is what's the automorph on Bonecrusher... does he even have one?
My second question is what's the automorph on Bonecrusher... does he even have one?