Controls and options changes aren't saving properly.
1. Options changes, specifically the music volume(haven't tried changing other settings), sometimes get reset after each mission.
2. Controls settings cannot be changed when using the "simple" scheme, even the ones unrelated to controlling the plane itself. Even if you change them, they seem to reset to default once you hit "return". (After this, if you go to options/controls again, they will visually appear to have been reset to default. Then when you change one of the controls again, all the other controls visually appear to suddenly change back to the ones you changed earlier. But this is deceiving, since once you hit "return" they will all reset to default again in the background.) This reset includes going back to the "normal" scheme and disabling "invert pitch", although if you change these in the pause menu after starting the mission, that will be saved properly for some reason.