Not Nude When Should Be
Sims that have clothes on when they should be nude most likely need resetting their bathing outfit using the 'ww.fix_sim_nude_outfit' command. You can use this command by opening the command console with CTRL+SHIFT+C keys combination.
Any accessories that are represented as clothes cannot be properly supported and will cause issues no matter what.
Top or Bottom is Invisible
Sims body overrides (default replacements) will conflict with each other, possibly resulting in invisible body parts. The only solution is to install just one body part override for top and bottom. This might be just the case for the CAS Screen, not the gameplay.