I have followed the steps here:
https://developers.google.com/cast/docs/developers
and am using this sample sender code: https://github.com/googlecast/CastHelloVideo-chrome
to get started creating a chromecast receiver app. I have my app id and when I change the sample to use my app id it returns "unavailable" in the receiverListener event. When I use the default media receiver app id it works just fine.
Is there something I am missing?