Hi Patrick,
Well I don't have a resolution for you, I do have a similar problem. I work on 600x800 and design all of the forms for an older system at 640x480. I have noticed that SOMETIMES the forms are so high up on the screen, that the menu is not even visible. They have never been to low though. I set .autocenter to .t. on _screen and I even tried setting .left and .top. The funny thing is that if I change my resolution on my monitor to 75mhz instead of 85mhz the problem goes away. It is not consistent. I even tried designing with my screen resolution set to 640x480 but it does not seem to change anything. Also, it is not persistent. It only occurs sometimes. I will really be interested in what you find out!
Tracy