Everytime I use Alt-Tab to enter fullscreen mode, the colors become inverted in whatever program is up. If I am at the prompt, the blue background from the "Welcome to DosBox" becomes red. If I have a game up (I.E. Warcraft), the colors are all inverted. I have to be in fullscreen and then open the game. It becomes annoying when I am wanting to look at the console. If I set fullscreen=true, the blue background still turns red.
Windows 7 RC1 32-bit
AMD Turion X2 Mobile 2GHz
Open DosBox 0.73 in windowed mode. Hit Alt-Enter. The blue should invert to red.