Made an account to post as well:
I'm in a very similar situation as reported.
I did remember a Windows update shortly before the issue started happening.
I've been able to sometimes get the keyboard to work again by remove the device from the system, reinstalling, and launching the game.
I believe the windows update did something to the USB drivers because I also get a few USB error messages every now and then, which never happened before the update.
I'm on Windows 10 64-bit and use a corsair k65 keyboard.