4k Screens and hi-resolution patch seem to create conflicts with most screen resolutions, resulting in very ugly screen and interface. If someone know of a way to solve this...
Ok, I found the problem! Strangely, there seem to be a conflict with games and a new windows feature to tweek the interface to appear larger that it really is. I have it at 200%.
In order for the game to work without flaws, you have to apply some compatibility tricks to BOX.exe in the file properties. As shown here. Sorry if it's in french.