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I tried, but it didn't work. I started playing from the save where I only took the first Dwarven town – the earliest save I have. And I don't even plan to start over, the game is quite difficult, and I spent a total of 7.5 hours on the playthrough.

Are you playing the original version or are mods installed?
You should understand that mods and maps (mods) can affect the gameplay of the scenario, leading to crashes. If you have fan-made mods and maps installed, leave only 1 of your maps in the maps folder. As for mods, remove those that cause conflicts.

Added after 43 seconds
Overall, the scenario is working. There should be no crashes.