Just like the title says. I have my Steam and games installed on D:drive. Got the game working just fine when I tried installing it through the launcher to the C:drive. However, I don't want the game let alone my steam folders on my C:drive and I do want the game to be linked to Steam (which it wasn't here as Steam did not register play time etc.) so the D:drive is the only option. I have also tried deleting the launcher files (just reinstalls them automatically when launching the game from Steam), disabling Vsync (did nothing) and ticking the "disable fullscreen optimization" from the ck3.exe properties (did nothing).
I would also like to add that some years ago when I purchased the game it worked just fine on the D:drive.
I would also like to add that some years ago when I purchased the game it worked just fine on the D:drive.