Whenever I try to make a gamebook or text adventure the OK button is always grayed out, making it impossible to move past the game creation screen. Yes, I filled out everything. Game type, language, name, and file name. Not sure what to do.

are you using HTTPS:// and NOT http:// ? (Assuming you are using the Web version and not the desktop one.)
Looking through these forums is the smart thing to do which will show you what others have found before you.

(Assuming you are using the Web version and not the desktop one.)

As they list filename as one of the fields filled in, I assume this is the desktop version.

Things I'd check would be whether the chosen filename is valid (doesn't contain characters not allowed in filenames, like /), if a game with that filename already exists, and if Quest can save it (not on a read-only disk, and the user you're running it as has all the permissions – I think sometimes it is necessary to run it as an administrator, but I'm not sure).