Hi there Matt,
Thanks for getting in touch with us, and sorry to hear about this problem 🙁
I just tested the plugin (Maintenance version 3.2) with default theme Tweenty Seventeen and The Events Calendar. Everything worked as expected, but I did see a JavaScript error in the browser console from a js file from the theme.
Not sure how the plugin works, or what are your site needs. Depending on these, you might want to tweak the plugin options a bit (maybe disable the front-end login form), reach out to them to see if they are aware of the problem or just use a different plugin to achieve the same.
Also, while I couldn’t find any other customers reporting problems with the plugin I could find some cases of other customers using it without trouble.
Please let me know about it,
Best,
Nico