I followed the upgrade instructions exactly - closed the board, uploaded everythign to the appropriate directories in ascii mode, used the Upgrade button, updated member post history, then rebuild forum stat files, opened the board. I have since repeated the whole thing twice, I also tried the ultimatebb.cgi file from the full version. I also tried it uploading in auto mode, no difference whatsoever. every test file works, all the path tests and whatnot still come back fine. The cp.cgi works fine, nothing reports any problems - it's just acting like the ultimatebb.cgi file isn't a valid file/script!