Custompress 'has archive' not working

First off, great plugin. I'm trying to use it to make several different directories on my site in addition to my blog and substantial e-book, one for student groups and activities, and another for free events. I obviously want an archive page for each, so users can browse and search each directory. (I didn't want to use the Directory plugin since I didn't want to switch themes

My problem is that when I create a new post type and check 'has archive' 'true', regardless of whether I give a custom slug and of whether I'm trying to edit an existing post type or create a new one altogether. My theme folder is set to rewrite, as well. Is there something I'm missing? Another folder to enable rewrite on, perhaps?

Ultimately, I want to have two new post types and two new archive pages.

Thanks for all your help!