Installed the game, let it update, clicked play and it just sat there with the play button greyed out.

Same thing happened to me. Apparently im missing a .dll file going to try reinstalling it to see if that fixes it.

Reinstalling did nothing.

same thing...

me too

I got it working. Try updating your DirectX.
First time i ever got that error so i had to do a little research.

I cant post links so google search "DirectX End-User Runtime Web Installer" and you should see a a link to download DirectX End-User Runtime Web Installer from the Microsoft website. Go there and click download. Thats what i did and now it is working fine.