I tried to do mine again and this is what happened:
Open Model -> Run Script (v1.5a) -> Add Everything on the list -> Tick the 'IK to FK' option -> Click 'Parent' -> Click top of the arm -> Click Bake -> A clone of the original model is made -> Max Listener window opens up empty
So the tools did make a new arm, but the new arm had no animations. It still does not work for me, am I doing somthing wrong?
I checked out your test result, and indeed it is better, but some parts like the torso still have far more keyframes than is nessesary. If possible, try to make parts like that more accuarate as well.