Game closes when leaving CAS using the check mark

Hi. I was wondering, has anyone else had a problem with the game closing out when you use the check mark to exit CAS? It's been happening the last few times I've gone into CAS to change my sims outfits, so was curious. I do have mods (MCCC, UI Cheats, Better Build Buy) and cc Build Buy; only CAS cc I have is Kitsule's pointed ears. Thanks :).