That's pretty clever! Using linked lists (like tree nodes in this case) to have the body move and attach. Are you going to make it so that it works for any angle, like say, from the side of the character instead of top?

Yeah, that is already in place via offset variables that allow child bones to be attached at offsets to the parent bones. Also the center of the object is in seperate variables, so that can be separately defined. Indeed, this is used in this character, as you can see by the motion of the feet, which would not be possible by simply rotating the childs, the offset is being set and reset each frame.

It actually works better in Greenfoot2.0 and i have updated it accordingly, i plan to release a new version rather soon since i am using it in my new game :)