To add to what was posted:

The files that start with "M" are files that have anything recorded to the melody and/or soloist tracks; otherwise, it's an "S".

An MGX file indicates that a multi-track MIDI file has been loaded into the melody and/or soloist tracks. This generally happens when you import an MIDI file into BIAB. When you do that, everything goes to the melody track and the flag for "multitrack melody" is set, and which can then be moved to the soloist track if desired. Normally, when you do this, the style for the song is disabled (you'll see an "X" in front of the stylename), but you can re-enable it.

So when you have "multi-tracks" on the melody and/or soloist track, and then go to save the file, it will save as an MGX file.

John

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