* The only thing that had an issue was when creating a new RigidBody, BulletXNA didn't know the type SimMotionState and the upcast type is unknown in the constructor. Therefore, I had to update the IMotionState with a new method 'SetBody'. All of the duplicated type information has been removed and BulletXNA is not relying on any non-standard types external to the library.
Necessitated allowing simulator and physical position of a body to
get out of sync since Bullet assumes that <0,0,0> is the center of mass.
Update DLLs and SOs for the UpdateChildTransform so positions of
individual prim in a linkset can be implemented.
Copied BulletSNPlugin.BulletSimAPI to a new
BulletSPlugin.BSAPIXNA.cs and then modifyed the latter to
comply with the BSAPITemplate definition. Not totally debugged
but the code is all there for an INI variable to select either
unmanaged C++ Bullet or the C# version of Bullet.
Robert Adams