I've extracted a head .nif from Skyrim BSA, then exported it as an .obj through NifSkope. Imported into ZBrush, edited a bit ( just smoothed a few things here and there, was careful to preserve the vertex number) and exported as an .obj again. After i inserted it into the .nif and saved, however, the Creation Kit (and Skyrim itself) freaked out on me. The new head showed up way above it's rightful place, so to speak.

Screenshot -
http://img861.imageshack.us/img861/6683/26111660.jpg

Though I have 3d modeling experience, I'm still new to NifSkope - so I'm most likely making a mistake, and probably an obvious and stupid one.
I've noticed that the "Center" parameter in NiTriShapeData is off (should be X:0.0003 Y:2.8057 Z:0.2472), but I have no idea how to change it :

The mesh appears normally in NifSkope, though.

NiTriShape -

http://img687.imageshack.us/img687/5650/nifscope.jpg

NiTriShapeData -

http://img24.imageshack.us/img24/3716/nifskope.jpg


Was it ZBrush that changed the mesh position, or does it have something to do with a corresponding .tri file?