Sorry about that. I assume you are not using a Daz unimesh? The error you mention I think is related to Poser(4567) figures (unwelded). Too many variables..

I should have asked which figure, which ZBrush, which Poser prior to answering... all have a "fatal" error awaiting for those who part from the path.

IF you are using an Unimesh, P6, UVmapper and ZB2,,, I'll be happy to talk you through it in an IM. I do not wish to post misinformation anymore.

If you are using unwelded mesh,, I can't help