Well UTC 0 would definately mess with your game times. They would be off 5-6 hrs.
Next problem is that Wisc. wasn't formatted as a State in the world.xml. Perhaps one of the xml tags was missing, that's why it's not showing as a State in your game and you can't edit it.
You could add it, but you'd have to re add the cities and most likely have to delete them from Wisconsins Nations screen. Lot of work.
Best bet would be to fix the world.xml file if that is indeed the problem.
Then you can manually reload the world.xml file, but I have no clue if it will work with an existing game. You can reload it from the Game tab "Database and Info and Tools" screen. Just click the tools tab and select "Reload world database from xml file".
I'll look at that file again and see if I can find where the error is.
