As I was setting things up, I prototyped it on my server (like I always do) and it looked great.
Then I installed the them on the production site and noticed there was an upgrade for the theme, so I ran it. Lo and behold, the menus on the top weren’t working.
Since I can be pretty scattered about changes; and because modifying a theme to support WordPress’ built-in menus has become second-hand to me, I thought maybe I had forgotten doing that step. But no, that wasn’t the case. In fact, when I upgraded my test site, the problem appeared there as well.
But the upshot is that one word reversal in their function code made all the difference in the world.
If you are experiencing this issue, find the line that reads:
…and change it to…