I run 4 different sites that work in tandem and updated all four at two different times of the day.
I updated the Catchbox (Free) Theme this morning on two of my sites (along with WP 4.5) and then updated the other two this afternoon (along with WP 4.5).
The Customize features are only fully loading on one of my sites. Those that don’t load, pull up a partial page that want me to “Upgrade to Pro”, it shows widgets, and identifies the active theme as “Catchbox”, nothing else. (http://wnccumc.org; http://leadwncc.org; and http://mission.wnccumc.org)
The one that loads (http://vital.wnccumc.org), has a full menu for customize, however, on that site, I had the default page to show content on right, and it will only show on left.
Not sure what is going on, but there are some obvious kinks in the theme update.