in the options - preferences - Realtracks, you need to tell BIAB where the RTs are - see picture below. Then you need to do the same for the realdrums.

Attached Files (Click to download or enlarge) (Only available when you are logged in)
Capture.JPG (46.95 KB, 67 downloads)

Retired to Make Music - No Plan B
My SoundCloud
Preview My Current Project .