I wrote a code (see the attached example) using the FullScreen option.
It works fine on the device but I got a wrong (unexpected) result on the desktop.
The form size on the desktop seems to be shorter (268 pixel height).
This is a different issue. FormLib.FullScreen doesn't change the screen size on the desktop.
You should add a form with the designer and choose Tools - Screen Size.
Add 52 to the height (should be 372). These setting will not affect the device and will affect all forms.