...when I open one in BiAB, nothing loads. I'm guessing that the files that make up the .SGU file are missing.
So that we can get a better picture of your situation, could you please answer the following questions.
1) Do you open BIAB and then open the SGU file by using "File | Open"? If you open it in a different way, how do you do it?
2) When you open the SGU file, is the chord sheet filled with chords?
3) When you open the SGU is the mixer populated with instruments?
Regards,
Noel