Confluence Email Gateway does not Work

Problem

Confluence Email Gateway does not seem to work at its fullest. While it is not documented I believe every plugin available at Admin Panel, with possibilities of editing and altering is supported if not installed by 3rd parties is (or should be) supported. Therefore this plugin does not have a documentation nor seems to work correctly.

Undocumented Features

This plugin lacks implementation, and Documentation. Thus it is also required a documentation for it, whether it is supported or not.

Answer lacking Official Response

There is no Official Response to this Answer: What is Confluence Email Gateway?