I'm trying to play a hard or very hard SS Campaign with my friend (hotseat in a single PC, not online) but after we end first turn the next turn the game sets the difficulty to Medium (SS message pops up).

Tried to google a solution but the only thing I got was a guy talking about editing the "campaign_script" in the SS folder, but he does not especify which file to edit.

Anybody care to explain how to fix it?