Attached Link: http://www.curiouslabs.com/

You're running into two possible problems: 1.) You have too many items installed (I believe about 250 in a given category is the limit). The best answer for that problem is PBooost. It costs about $20 and I think you can find it in the Renderosity Marketplace. 2.) Poser Pro Pack had a problem with long filenames. That fix was handled by the latest Service Pack. I've provided the link to the Curious Labs site for your convenience in case you need further research.