The graphics library that I'm using takes care of the window size. I'm migrating to a new version now, maybe they have fixed something. I can send you a Steam beta key so you can check it out easily.
Sure, can you just tell me at which point it's black, do you get past the main menu?
Please send me an email from the same email that you used to buy the game, cause in my records I don't have the one that you used to sign up for the forum.