I've been experiencing some weird effect. Two glasses i downloaded from Virtual Rooms have black disks in them, namely in the base of the glass. They only appear when I render the image, and not in any of the preview modes. The black Disks appear only inside, when the glass is transparent. Has anyone else experianced anything like this before? The glasses are OBJ and are made of 1 material and when exported to 3DSmax they look fine. Even if I then export them back as 3ds files to poser they still have the black disks. Can you help?

Possibly, those disks have their "face Normals" inversed! If you fell confortable with the "Group Tool" in Poser, just select those faces and inverse their normals! Or just assign a New material to those faces again with "group tool" and just make it 100% Transparent in Materials editor...