To answer your first question, I can direct you to this link:
https://code.google.com/p/play-games-pl ... ail?id=108
As for what you said, the cocoonjs plugin coming months not having support. At the moment it is only hidden in the options of the construct, but with the plugin on github and they keeping this exporter in the list, it will still be possible to use it until it is too outdated.