Yes, Prof, when I hit the NAV button to the top left of the screen, it returns me to the map of me and where I was/am. I think I will have my wife play with it with the instruction manual handy, just to make sure this is not simply a matter of operator error, an adjustable sensitivity feature, or a simple failure to read the manual thoroughly. Yes, I admit it, I should do a bit more reading and playing with the features.
Re night driving, don't turn off the power to the audio, NAV, DVD. Go to the screen brighness features (Day, night, auto). I think there is an off feature as well which leaves the screen black. The audio continues. Any button controlling the audio, DVD, or NAV that you touch turns the display right back on.
PJ