The top part of the main viewport is totally white.
Either if I'm in the Project/View/Layout or Plan/3d/elevation. I never see the top part of it.
I tried everything: hide palettes, deleting add-ons, reinstalling, installing a trial version. Nothing worked.
The only option that works is reducing the window height to a very narrow space. The blank space dimension is related to the height of the archicad window.
I'm on macOS Sierra 10.12.4 - macbook pro Intel Core i7 + Intel Iris Pro 1536