I had a similiar problem with Vue 6 right after I reinstalled everything on my new laptop.  It wasn't Vue, it was Poser 6.  Go into the Edit / General Preferences dialog and click the Misc tab.  Make sure that "Use External Binary Morph Targets" is not checked.

You may have already done this, but it fixed the problem for me.  There's also a limit to 1 dynamic cloth item per Poser file when importing to Vue (for me at least).  I always run the first dynamic cloth sim, export the completed sim object as a wavefront .obj file, delete the original, then load the .obj back in.  The only downside to this is that is can have some texturing issues, but I usually use Vue to create textures anyway, since Poser MAT file textures eat up Vue memory resources.

Like I said, you may already know all of this, but if not, I hope it helps.

Darkwolf