When MBAC first fires up, there's a button in the dialog box to manage advanced options. I know the first two pickboxes are the texture quality; the next is the game speed in frames per second, and of the three checkboxes, I figured out the first one is to give the game more CPU time/priority, and the second is to display or not the current frames per second on the title bar of the game when running windowed. But I have yet to figure out what the hell does the third option do. Help please?