Thanks, Ed.

I've got \BB\Drums and \BB\RealTracks folders on Drive C and on Drive F, but the Drive C copies are empty apart from a .txt file in each. I erased previous versions of BIAB completely, and installed from scratch, including all the RealTracks, when I upgraded to 2012.

It would be odd if BIAB did the sensible thing for the RealDrums and not for RealTracks, if it didn't find the files where it expected them to be.

I've noticed that if I double-click on one of the imported files in Windows Explorer to open it, generation of RealTracks goes ahead as if I'd opened it from BIAB and hit Play=>Generate, and the song is played correctly,

I've tried looking at a hex-dump of one of the problematic files, but can't spot anything that looks like an explicit reference to a folder such as C:\BB\RealTracks - presumably the RealTracks section is compressed.

I'll try renaming C:\BB\RealTracks and see what happens.