On May 7, 2012, an AG Custom Admin update notification appeared on my admin page. I immediately installed the updated version. I then logged on as a subscriber to my site, and the entire admin bar is visible. I logged back in to my site as the admin, checked the settings, and then checked it out again as a subscriber. The admin bar is still present.
I re-installed the previous version of AG Custom Admin and the admin bar disappeared like it should.