Appears that I can't maintain enough friction on the ball joints. Since repair involves me disassembling the entire structure to get access to the ball, it's near impossible. The legs are still operational, but posing is now limited to non-acrobatic non-aerial poses. I still have the old legs as backup, but that involves removing a small part of the hips (the ball and socket pin part) to allow them to be reused.
I also erred on the paint mix, so her legs are slightly off shade. I'll have to correct that later.