Just had run into regression that occurs in "King's Bounty: The Legeng" game when run under Wine (tested with versions 1.3.29, 1.3.30 and today's wine-git) with nVIDIA Linux 32bit drivers v.285.05.09 installed. Downgrading drivers version to 280.13 fixes the problem.
Problem manifests itself as "main game character and NPCs being not rendered correctly". Most likely it is some kind of depth-buffer issue as "not rendered correctly" in this case means "huge parts of the model mesh are simply not being visible". Pretty much that's it.
I had also spotter another regression in 285.05.09 drivers that happens under certain circumstances under Wine 1.3.29+ in Half-Life 2: Episode One (most possible there are places where it might be spotted in HL2, HL2:EP2 and other source-based games but I hadn't tested them so can't prove it). This regression manifests itself as incorrectly rendered "screens" when Wine's OffscreenRenderMode setting is set to "backbuffer". The "screens" I talk about are ones that had been causing huge performance drop in Wine prior to 1.3.29 (bug #13313
that was fixed in 1.3.29). I can provide additional details and savegame from affected place if requested. Downgrading drivers to 280.13 fixes this bug too.
P.S. I'm not totally sure who should be blamed for this bugs - nVIDIA or Wine devteam - but I assume that if the bug get's fixed by just downgrading driver version and not touching anything in Wine it is a good sign that the regression is in the drivers.