I don't have Comical installed so I can't test this, but you should be able to rename this file to .cbz, then read it with any digital comic book reader.

Index on DA is here
https://www.deviantart.com/arofatamahn/journal/Friendship-is-Magic-The-Night-the-Magic-Died-318852697
and the artist also has an FA account, and the full comic seems to be there too. You might consider going to the last two pages (135 & 136) and reading the artist's text, as he has a lot to say about the process of making this, and some good opinions about the show, and shows like it.