https://bugs.winehq.org/show_bug.cgi?id=44123
--- Comment #22 from Józef Kucia joseph.kucia@gmail.com --- Glad that the game finally worked for you.
The registry key is required because wined3d doesn't fully support OpenGL core contexts yet (see bug 38648). FWIW, we are considering adding a hack for Wine 3.0 to make the registry key unnecessary.