@Ink, Aye-aye! The latest driver from the 16th of July 2018 is installed and in use. I can try installing BETA driver from the 10th of April 2018 which is of a higher version number and see if that improves anything. @Dibbler, I can't do the tutorials because I can't see any of the mission items. Also, it makes battles really hard, because in addition to the water level being raised, the white areas showing the cannon aiming directions over the water are all jumbled up and don't point to anything. It's just a mess of white lines around my ship.
EDIT: @Ink, I tried both the latest stable driver and the latest Beta driver. With both, this graphical bug persists.