Agora-Project Software Won't Install

I was looking for possible easy use software to create a newsletter on our website. I found Agora-Project which seemed to fit the bill but I get "Installation Failed" (no errors or reasons given) when trying to install it. Other installs of software using Softaculous onto various domains have worked fine.

If this software is no longer available, can anyone recommend something else? My user who will be creating the newsletter is not very tech savvy and so it would need to be easy to use (not Wordpress!).

Thanks