Hey There,
Garageband won't allow me to add sounds to my Software Instrument. I've followed the instructions from:

GarageBand 5.0 Help: Adding sounds to the Sound Effects Software Instrument

and it doesn't work. Any ideas? I've heard that I can also edit the sound being played by editing a file that contains instructions on which file is being played, but I really don't want to get into all that. I think GB was letting me add files before I upgraded to Lion, but I don't recall exactly.

What I'm running:
Macbook Air
Garageband 5.0 (GB9)
OSX 10.6.8 (Lion)
1.6GHZ intel Core duo
2GB Ram

Thanks for the help!