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It was working on MINT 18.3, but I tried raising the graphics level to high just to see how well it would run. Now, even after re-extracting the files and starting over again, and then trying re-downloading the whole game and then re-extracting the files, the game just gives me a black screen after the three publishers screens.

The only way to get out of the black screen is to do a hard reset. Is there any place to reset the graphics to low or medium without starting the game?