Unable to install this app

I tried to follow the instructions, but they don’t match the reality on my El Capitain. I open the Notifications center, there is no EDIT button. So I click the cogwheel button which opens the Notifications Settings panel. Monity is not present in this panel. I tried to go to their Help page, and it is useless: the dropdowns open in German. I happen to understand German, but there is nothing different there. I just threw away $5.

tomjab about Monity, v1.3.1