Something seems to be going on with the Amazon App console. I have mine set up and working, but when I go back and log into the console, my app is no longer there and isn't registered. However, it is working!
Anyway, here are the best instructions I've seen so far. It might be good to make a video of it to help people out and show them step by step. Maybe I'll do that if someone else doesn't in the near future.