Oh. Darn. I thought I knew what Category Previews did, but I was wrong. I swear I’d just looked at it and it required that the category be visible and just mostly-hid the category. Maybe there is some other component that I found that I confused with category previews.
So, yeah. Probably makes more sense to use the well-known and well-supported Category Previews. I’ll update OP and, if I remember, the README.
Oh! Maybe it does have a reason to exist!? It’s possible that working with category boxes does give this a reason to exist. The only thing that I thought might be “better” about mine is that it does hide the previews from admins and group members as well as anonymous users.
Maybe I won’t delete it right away. 
