I'm on it, but issue 2 is not an issue.
I'm writing a doc file at the moment, showing you how to access the plugin expressions. It's a little bit confusing, I have to admit that. But with the docs updated, it should be clear then.
About issue 1, yes you are right. I already have sent a message to Imanol.
I checked the plugin code of my own, but I couldn't find an answer why it calls the "On purchase completed" action. So I guess it's something located in the cloud plugin "InAPP for Google Play".
I keep you posted.