event calendar by Alex Tingle – still supported?

My client’s site is using the plugin Event Calendar by Alex Tingle, is this still being supported? When I click on the link to the plugin site I get the 404 error, and the same for clicking on the links to their support and documentation pages.

If you know anything about this plugin, can you help me with some documentation? This site was not designed by me, and I can’t find anything that even tells me how to add an event. My client appears to be new to his company also, so we’re all trying to understand something someone else set up.