Except the installer requires one specific repo mirror to be up, which can't be customized, which has been down for weeks and the dev isn't very interested in providing any fix or workaround so a lot of people literally can't install it.
It's a bad suggestion, it's a beta product not fit for end user consumption yet.
Saying full source code leaked is a little wrong.
Plugin was always open source, and all plugins for that framework are required to be open source by the framework's licensing.
Doesn't change the fact that once one person did it, the code was available for anyone, though, you're right.