I think this is due to my wp theme, but even when Override Default Appearance is Unchecked, my events list is appearing with the styles of my theme's archive page, but the php of the event archives.
To get around this, I created a page template containing archive-incsub_event.php, and set the plugin's appearance theme settings to use it as an archive template. This worked correctly for viewing the root slug archive, but when viewing a single event category archive, it used the page template, but could not use the event plugin styles. I had to copy the front.css file into my theme's stylesheet to get it to work correctly.
Is there a better way to go about this?