https://bugs.winehq.org/show_bug.cgi?id=38104
--- Comment #1 from Sławek slawek@lach.art.pl --- I hate WinAPI and I programming in WinAPI many years ago, so I don't remember it. What I saw in logs, while setting WINEDEBUG=ddraw is" trace:ddraw:ddraw_surface4_Unlock iface 0x1d0584, rect (nil). trace:ddraw:ddraw_surface7_Unlock iface 0x1d0580, rect (null). trace:ddraw:ddraw_surface4_Unlock iface 0x1d09e4, rect (nil). trace:ddraw:ddraw_surface7_Unlock iface 0x1d09e0, rect (null). trace:ddraw:ddraw_surface4_Flip iface 0x1d0584, dst (nil), flags 0x1. trace:ddraw:ddraw_surface7_Flip iface 0x1d0580, src (nil), flags 0x1. trace:ddraw:ddraw_surface4_Lock iface 0x1d09e4, rect (null), surface_desc 0x6544dc, flags 0x801, h (nil). trace:ddraw:surface_lock This 0x1d09e0, rect (null), surface_desc 0x6544dc, flags 0x801, h (nil).
It looks like Seven Kingdoms 2: The Frythans Wars tries to unlock not existing surface and tries to flip into not existing surface.