I am not sure if this is a bug in the game, but I've reinstalled the game completely many times. Whenever I play a "conquer the world" campaign, after a certain amount of time the map becomes filled with the sea and water. Though the game is still working, I am not able to play because of the terrain. I've tried to google it, but I am not able to find anything about this.
How can I avoid or fix this issue?