Codaz: in MapThis 0.5+, every time you press a button you hear a beep through the speakers. I found this really annoying (it also slows down scrolling in lists e.g.), so I removed all those beeps.
About screen brightness, when I'm driving around, adapter plugged in, I don't want the screen to turn off automatically. I know you can set this behavior in the firmware itself too, but I only want it in MapThis, not in other programs, so that's why I built it in :)
I agree most users will probably not want to use all changes I've made, so anyone can feel free to remove those changes that they don't like from the source, and compile it themselves. You can find the changes I've made by simply looking for 'Nieko' in the source files.