Wasn't really using the plugin, although it was active. Wanted to give a heads up in case anyone else came across the same issue.
I noticed that posts and pages disappeared from view both on the site and in the dashboard (although the dashboard still displayed the number of articles posted etc.). I wasn't able to post new entries either. The database, fortunately, was intact.
I deactivated all plugins, and the posts reappeared. When I started reactivating them one by one, I discovered that it was this one was causing the problem.