Sorry for confusion. This should clear it up. Compliments from Matt:

There is a really good set of FAQ entries for PG Music products. Click on Support at the top of this page.

Here's your answer, from the FAQ:

http://www.pgmusic.com/techfaq28.htm#85

A lot of them are remnants from early versions. The two to know are .SGU and .MGU. When you enter only chords, it's .SGU. When you then add a melody, it gets saved as .MGU.


Dan, BIAB2024, SoundCloud Win11, i7(12thGen), 32GB, 1TB SSD(M.2 NVMe SSD), 2TB Libraries, 1 TB(WD-Black), 2TB SSD(M.2 NVMe SSD)Data, Motu Audio Express, Keystation 61, SL88 Studio, Reaper