MED (or any tool) - change base frame / pose of frame 0 ?

Hi all.

I finally managed to convert mocap data and retarget the bones of a model for Animation.

Now the arms are messed up. Iam pretty sure this is cause of different poses of the Frame 0 / baseframe or how ever its called.

Now i want to change the base pose of a mocap file.

But if i rotate the bone outside of meds "anim mode" only the bones are turned, but the mesh stays in same Position.
This also happens with fragmotion.

Is there a way to modify my base Frame / start pose ?

Big step Forward...its not screaming kill me. The retarget of arm bones ive disconnected cause the different poses will mess them up ( at least i guess its caused by the poses ):


Thanks for all tips and help.


edit: Ok found first workaround.

Ok...now i applyed the mocaps. But i dont know how to make this look better, shoulders are f* up:



Now i dont know any solution. I tryed to "layer" both files to fit each other...in the Editor it Looks like they do.
After retarget i got a lot of mesh deformations.


Anybody any idea?


Its crazy that recording mocaps and applying is a lot more easy then retargeting to another rig.

edit:
Well i think this is caused by too different bone placing. Without a pro i leave my hands off this animation stuff.