Yes, John-Luke is right, and it's very easy to see that it's a bug and no configuration issue:

1. Select style PNOSIMP4 (simple chords make it easy to see the problem)
2. Pressing C-E-G-B on your MIDI-keyboard.
3. Pressing ctrl-enter on your computer keyboard.
4. Band-in-a-box interprets this correctly as a Cmaj7-chord.
5. Save it as a MIDI-file and open it in a DAW.

When looking at the tracks in your DAW you can see the following tones in the chord:

C-E-G-B-D

This is actually a Cmaj9.

If you enter a Cmaj9 in Band-in-a-box you can see that it is executed identically. You never get any maj7-chords in any style in Band-in-a-box. The same thing applies for 7sus chords.

It's really a waste. Think about all those (24) maj7 and 7sus chords recorded by talanted musicians for all the RealTracks and they are never played. Nobody can hear them. Instead we hear the maj9 and 9sus chords.

Sorry to hear that this have been known for a long time without being corrected. It should be really easy to fix.

/magnus