I just made an object for tile-based platform games that can contain multiple bodies, all using rectangular collisions. It's really fast and should clean up a lot of messes in platform games that don't require the accuracy of MMF2's precise collisions with PMO, or games that have a lot of enemies that would have required multiple PMO objects. All of it is handled within one of this object.
Check out the example
I just made this tonight, so if you have any ideas, I'll try to put them in.