When I bought BIAB a while back I got a bunch of RealTracks and installed them all. But I find I'm really only using a handful. Is there an easy way to manage them (ie uninstall the ones that I don't use?).

Go to Applications/Band-in-a-Box/RealTracks and move to Trash the ones you don't want, make sure "Show RealTracks that are unavailable" is unchecked in the picker window as you will still have associated ST2 XT2 in Applications/Band-in-a-Box/Soloist.