Disable surround sound on audio drivers.
As of update 1.0.438.0, intro videos can now be skipped anytime after the first run of the game.
This should fix your issues with huge FPS drops that come from opening doors or cutscenes.
In Windows 8.1, sometimes the game will appear to start minimized, and any attempts at restoring the game will not work. Disabling Exclusive Fullscreen mode in-game should fix it.
It seems Nvidia have set the default Vcore too low on the 5xx/6xx series cards. They do pass stress testing but crash in a few Real World DX11 intensive games.
The game crashes while playing cinematics.