Another thing that can occasionally happen is having two texture files with identical names and Poser picks the wrong one. It doesn't matter if the needed file has a direct directory reference (or didn't matter for P5--I don't know if it was fixed in later versions). Poser can still choose the wrong file. You might want to do a search in your texture folder for the filename of the texture causing the problem to see if there is more than one file with the same name as the texture you're trying to use. If there is, move the wrong file out of the Poser directory to a temporary location, shut Poser down, and try the render again.

This is a long shot, but would explain why Raven's not having the same problem. Renapd wrote about this a while back when she was trying to troubleshoot why a customer was getting a bad texture. She couldn't duplicate the problem because her Poser tree didn't have the same duplicate filenames in her textures. I forget how she finally figured out the solution, but it was due to Poser grabbing the wrong texture even though her texture reference used an absolute path to where her product installed the files. The solution was to give unique names to her textures to minimize this bug cropping up. As to why this is not a more common problem, I don't know. Lots of textures use the same filenames and it's not usually an issue. Every now and then, it is.

My visual indexes of Poser content are at http://www.sharecg.com/pf/rgagnon