BucklingSprings

I had the same issue. I tried looking for the settings file, but had no luck. I managed to fix it by temporarily setting my resolution to the highest possible setting, then starting the game. I somehow managed to close that DLC window after I tried switching to windowed mode with ALT-ENTER. One of the buttons on the left of the screen (still only partially showing on my screen) brought me to the graphics settings. Kind of a clumsy fix though.