When I try to open custom content clothes it only shows locked items.

When you first open the game, before loading a save - do you get a pop-up listing what custom content you have installed?

Although - interesting note - I hadn't tried to turn my cc/mods on since the HSY patch because I couldn't get the non-modded game working well enough to bother, but when I tried just now to give you a screenshot... my game actually didn't show the pop-up.