Ooh - it's my first post on Renderosity (be gentle with me!) Gweb, one workaround I've used to get some physics influence with an IK chain is to set up a helper object in the scene - just a normal cube, positioned in the same place as the IK target object (in C4P), and with the target object turned into its child. You can then apply physics to the cube and the IK target will follow it - just make the cube invisible for the final render. Got the same thing to work using the last bone in the C3 IK chain before my upgrade arrived. I've not experimented with anything more sophisticated than this, but that's my thought - let us know if it leads anywhere and if you find out anything else useful...