[gong]

Now with flip1314 suggested settings, the opening KSM screen is perfect, no grey bar inside the bezel. However when I enter "scripts" menu for instance, the bottom inside the bezel is greyed.

EDIT: South orientation is as good as North's;
East is too low (grey area inside the bezel on the top + bezel not visible on the bottom);
West is too high (grey area inside the bezel on the bottom + bezel not visible on the bottom as well).

All comments are in regards to the opening screen.