No worries. I try luck and intuition sometimes. I won’t assume anything. And you may need patience with me. Do you know how to get to the Run function on Win10? Forget myself sometimes.
Think it’s right click on the big icon lower left corner. If you can find that, type in %appdata% and it’ll bring up some directories. Navigate to the OOTP one and click on it. You should see a Config directory then click on that to see some cfg files like app.cfg and engine.cfg
Let me know when you find them or if you have trouble finding them.
Edit: oh, and did you alter to the 1600 through the game or your Win10 display settings? I’m thinking you did it in game settings. Not sure.