Are you using old calculations for corruption? I was playing around with the palace location in the corruption tab, and the best spot for my capital turned out to be an isolated and currently useless city I only captured to get a luxury. This would make sense with the old rules for rank corruption, but not in PTW or C3C.

Right now it only works with single player - another way you can exit out is if you click yes to the warning, and then quickly hit Alt - F4 (exit).
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