Reset XForm didn't fix this? I'm at a loss. I have seen parts export incorrectly but the problem was always easy to fix. Note that many times it was not possible to preserve the animation (ie. the animation was screwed up and had to be redone.) I learned the hard way to always do test exports at every major step (and that certainly includes just before I start animating) and to always Reset XForm immediately every time I mirror anything. If you work "blind" and just assume it will export correctly at the end you are setting yourself up to have a lot of time and effort wasted.