Default S4S skin overlaps creations?

Hey guys! I have a problem that I'm guessing is quite simple. I've tried looking through the tutorial index and searching up what I need, but to be honest, I don't know what terminology to use. My problem is that whenever I create a CAS part like makeup, tattoos, skin details, etc. the default s4s skin shows up over what I'm trying to make. It's fine in game, but I don't get to preview any of my creations... which would be nice. xD I really have tried trying to find some info but I'm a bit clueless to be honest. Does anyone have any advice? I don't know if I need to screenshot anything since... I don't know where the problem lies, haha. Any help appreciated, thank you!