There are 2 kinds of .rsr files. (The name might allude to the "resource" fork present in Mac files since Poser was originally a Mac application.) There are "rsr"s in with the Geometry files. Don't touch them unless one gets corrupted. There are also .rsr files present in the Libraries for characters, lights, props.... They replace the shrugging guy with little pictures of the desired object. When you install ProPack it automatically goes in and converts all of those .rsr files to .png files as each library is opened. If you see a character folder which has .cr2 .rsr and .png for each character, you can delete all those .rsr files. Don't delete them unless they have been replaced. I did mention two types of .rsr file. If you use the DOS command line and delete all .rsr in Runtime, you'll remove too many. Don't do this! Think first!! Only remove the ones which have .png's in the folder next to them. You wouldn't think that a few thumbnails would take up that much room on your hard drive. People here brag/complain about how many gigs their Runtime occupies! If you are tight for space, or naturally tidy, you can free up a lot of space for something better than redundancy. And in case you are wondering, .png is a standard cross-platform, non-lossy, really neat file format so converting is a good idea. Carolly