As stated in subject - by unknown reason, during playing in single scenario, at some moment after finishing my turn game is crashing and it looks like on the picture I've attached - there is this icon, everything is "blacked" and I can't do anything despite ctrl+alt+del to close Eador. And it's always about this "critical" turn, because when I'm trying to load a game and go again through it, it's crashing in exactly same moment.

Once (but only once) I've managed to somehow pass through this bug, I've decided to stop movement of my heroes and send a diplomatic offer to one of the masters. But unfortunately, it didn't work in case of next "critical turn".

What's the reason and can I fix it? I've lost one scenario in this way and I would be unhappy if this one would be lost as well. Many thanks for help!

There is one cause of crash I remember, some counteractions with soul drain. Maybe AI attacks someone and triggers it.
Try to build a road without defenders between you and ai, maybe it would overwrite his priorities from triggering crash to attacking you,

Unfortunately, didn't work (none of my heroes can't get to enemy's province in one turn). I'm guessing then that my scenario is lost :(