same method, but in video form.
https://www.youtube.com/watch?v=6ebiyOtn7NA
Edit: Yep, restarting did the trick. Have media apps without Chromecast support suddenly become Chromecast capable? This is pretty awesome.
Edit 2: Why yes, yes they have! Now if only I could stream audio only ...
Screen casting with Youtube is a good benchmark of screen casting. Of course, for daily use you'd want to cast from the app directly.
The first and the third links are the same - did you mean to post only two?
same method, but in video form.