Hi Mark, first off all thanks a lot for answer me, im going to send you this photo, when you can see that the nav/gps switch in the 737 is "attached" in nav mode, even if i use the the default flight planer. I can't turn it into GPS.

in the other case (727) , i dont know why after all afternoon "tweaking" the panel i make it, the plane now follow the gps when use "shift+N".My Fsx-se, is located in C:/ x86/ Steam/ steamapps/ common/FSX. I've to say that i only have 1 hard disc (1tb)