I'm not exactly sure what you mean by customized RealTracks, other than having just moved the ones you use on a regular basis to the OS drive, and presumably all of them are still on the external USB drive?

When you upgrade to 2016, and you select to install over the current location, it will overwrite your files with (most likely) the same file that was already there (RealTracks don't change much, unless they were "fixed" by PGMusic for some reason); even then, it's usually the text offset descriptors that are changed, not the audio files themselves.

It won't look at your current configuration, however, and say "I'll just install the files I already see there.

That being said, you could upgrade to 2016, then do one of the installation options that leaves all the RealTracks/RealDrums on the external USB drive or whatever alternate location you specify. That will leave alone all the files you have on your OS drive. You can then go through the same process as before to move over the new RealTracks you might be interested in to your OS drive. That preserves the larger set on the external USB drive, and let's you just use the ones you want on your OS drive (after telling BIAB that's where they're located).

I hope I made sense, or did I miss something here?

John

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