hborre, it is installed in Program Files.  I don't think the permissions thing was the problem (read below for my fix) because I had problems with Sketchup trying to write to the program files folder and the files ending up in a protected folder, part of UAC I think.  Anyway, I have all the software that might do that authorized to write there. 

Anyway, I think I have found a fix that people might want to try.  I knew that the library was displayed using flash, so one of the first things I tried was updating to the latest version of Flash in my default browser (firefox).  But that didn't fix it.  For some reason I tried the same thing in IE instead.  That seems to have fixed it for me.  I'm not sure why, but it worked last night and was still working when I loaded Poser just now to double check.  So I'd be very curios if that helps the other posters who have a similar problem.  Give it a try and post back if it corrects it for you guys as well.