Two programms or windows running at the same time, black screen after game loads and menu music playing.

[Bento741]

When I try to run the game, another programm also runs. This other programm or window shows all the archives of the game when the game is loading and the game window turns into black screen while the menu music is playing. My Windows version is 10. I dont know if i am right but this other window looks like a command prompt. 

[Beard]

This is normal, its just the game console that runs in the background.
This has been removed in the future versions, but is still around in the current public version.

[Bento741]

But how can I fix the black screen in the menu? Because I cant play the game.

[Beard]

You have a black screen? In that case try disabling the Steam overlay:
 

Open the Steam client and navigate to the Steam > Settings/Preferences > In-game tab. Uncheck the box next to Enable the Steam Overlay while in-game.