What is your RealTracks folder set to in Options > Preferences > Song Generation c:\bb\RealTracks\ or an external drive ?
You should have wav & wma as well as the bt6 files.
I think in the earlier version that you have there was only nature loops and some Tambourines.
You can get plenty of free loops on the net just put them in the loops folder and enter the setting for the loops if they don't show, the later version read the loop info from Acid loops.