Attached Link: http://www.soft-rabbit.com/

Found it. From Daio: use my quick and dirty cheat. Create a .cr2 file (or any poser library file except a pose file) with the thumb you want on the MAT file. Run that file and your MAT file through MacConvert using the Export to PC function and make sure to check the "Delete Macintosh resource fork" box. You'll end up with 4 files a .cr2 and a .rsr and a .pz2 and an .rsr. Delete the .cr2 and the .rsr file from the MAT pose file. Change the name of the .rsr file from the .cr2 file to match the MAT file. Run the .rsr and the MAT file back through MacConverter to create a Mac MAT pose file with the correct thumb. Not as good as having the original RSR, but better than the Grey Shrugging Guy. BTW, I'm adding the URL for Martin C's invaluable free Mac utilities, in case you don't have them yet.