Can not make aliens

I am currently experiencing an issue in CAS. When I go to pick and occult to turn a sim into an alien my game freezes and then the screen goes white. Same with adding an alien from the bar at the bottom of the screen. I made a vampire family recently where this was not an issue so it seems to be just the aliens. When trying to find a solution I found a Reddit thread of others experiencing the same issue with aliens including players that do not use any mods or CC. I do use mods and CC, but all are up to date and my game is updated. Was really excited to make an alien, but it just is not working.