Hello, I recently had this problem with Dimension Pro and the E-Mu Proteus pack on a which wouldn't show in the programs list. Also, hitting F5 didn't help as the DAW i am using had already that hotkey assigned. I finally found this solution that worked on my Windows 7 64 bit.
Here is what you must do if you have this problem:
1- enter the folder C:\Program Files (x86)\Cakewalk\Dimension Pro\Programs.
2- find a file called programs.lst which should be about ~1mb (depending on how many programs you have loaded)
3- delete it (this is only a cache file which holds the program paths so don't worry, it will be recreated)