Returning to the original question: in terms of importing V4.1 into Carrara, in your General Preferences, do you have Use Binary Morphs unchecked when you save the Poser file?  I don't do animation, but I have imported V4.1 for still scenes without incident.

If I try to save V4.1 with binary morphs, I can't even open the Poser file later in Poser itself.