Hmmm, did you UVW-map the sword when it still was a Editable Poly ?
That would be my mistake really :-s
Its better to first convert your model to a Editable Mesh and then UVW-map it.
If you still get troubles with stretching and such, do the following.
1) After UVW-mapping, convert again to Editable Mesh: your UVWmap won't be lost it'll get "baked" into the model.
2) Now, use the select Poly in the Editable mesh. Try to select parts(part by part) of the model like you UVW-mapped them. Its a bit of a memory game
3) Hit Detach, make sure to put By Element on
4) So remembering your UVW-map a bit, go around your model and Detach.
5) If your model was linked to the aurorabase, best break the link. Then do the ResetXform and relink the model.
6) Export the model out again.
This helps me out most of the times, how many parts you need to Detach depends on the model.
Sometimes I only needed to do one to fix a model, other times I needed to Detach all the parts.
Hope this helps