Solution, known working for this problem:
1.) Backup saves
2.) Reinstall the Game: King's Bounty (even Patch it if it is applicable)
3.) Reload old saves - move out of area, return back to area... all works fine again
4.) Should steps above not work - but you found other/new solution - send me private message
Otherwise please try contacting Atari / or 1C Company tech support (This Forum is mainly for free discussion/ can't guarantee solutions)
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