I cannot get this working in Windowed mode.

Mouse is also very erratic, klunky and IMHO unplayable - in both full screen and windowed mode, in both non-UH and UHD resolutions. My level of frustration and irritation peaked only 20 minutes into the game. 13 other games I play on this rig w/o a single problem.

Any fixes for these issues or will I be stuck waiting for a patch.