Re: Running
This one would be alot simpler if there was some intermediate force that could be applied besides extending and contracting the joints, something like a half extend.
The player models I rig I usually set at least three controls for each joint, and tend to use the 50% marker extensively in running animation, I have to think it would be vital to getting a really smooth run going.
Ah, but I see how that would complicate the game interface, and admit I don't quite understand the joint holding modifiers just yet.
Exceptional attempts considering these points.