Attached Link: http://www.schlabber.org/index.html

I think you should be able to use the joint editor to change the center and rotation parameters. I usually try to position the weapon and parent it while the figure is in the default pose. Go to Shlabber's site. he has a slew of sword poses as well as gun and dagger poses that may help. I get the sword in rough position, parent it and then apply a pose and tweak the grip using the hand camera.

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