“Heroes of Might and Magic V: Tribes of the East”

Hello!
Sorry if I'm posting in the wrong place...
I'm having a problem in the very first mission of the campaign: in the first week of the second month, a part of the map with a red hero is revealed, and the game freezes... No matter where I go or what I do. (I've tried several options). At the same time, the save file gets corrupted. I've already lost all of them :((
Can you suggest anything?