Single Status Update
Would you by any chance have a working link to the Guillame Fradin tutorial you reference in your video here?
I believe he took them down. (I should probably remove it from list)
The mocap blender is a nice little OTL, but I think Michael Goldfarb's approach to binding a rig to an animated BVH skeleton is easier to deal with.
He used the BlendConstraint tool in Simple mode while only applying the bind to the ROT and SCALE. POS is left unbound.
Consider this follow up post which is a reminder to align BVH T-POSE or A-POSE (rest pose) to the target rig before attempting the BlendConstrain process for every bone you wish the BVH to drive.