There is one category I cannot delete. It is marked as "default" and grayed out.
The first category I created, "Comments about the film," had no posts on in it, but when I started to associate posts about upcoming screenings of the film with events (using the Event Calendar 3.1.1._rc2 from iCal (OSX) created by Alex Tingle), those posts began showing up in the category, even though I didn't want them to be there because they were not comments about the film. Also dates when any posts were made are now appearing in the calendar as active, even though I had not be an event on those posts. Those active dates link to a page with posts that were made that day, evem though there were no posts about screening events on those days.
Today I added a post that was a comment about the film, but couldn't check the category, "Comments about the film," for it was grayed out. So today, in Manage/Categories, I changed the name of that category that contained the posts with scheduled events to "scheduled screenings" and I created a new category called "Comments about the film," and I as able to associate the new post with the comment about the film to that new category.
In the plug-in page, I followed the link on the plugin page to the developer's site, firetree.net and sent two emails to the only email address I could find on it: firstname.lastname@example.org to ask about this. No reply yet.
Now I see one post in that default category, "scheduled screenings" that does not have an event tied to it. I would like to delete the category, but cannot.
The blog is at http://livingyogamovie.org/blog.
Hope someone can please help.