Custom Content Not Working Properly - Sims 3 CAS Demo

Hi,
I wanted to pre-download some custom content before I got the Sims 4 for xmas, so I put it into my mods folder (in the Sims 4 CAS Demo folder) and when I tried to put it on my sims, it mutates them. It's hard to explain but it's very much like the way cats and dogs would mutate in TS3. I'll include a screenshot. The custom content was from TSR and had been downloaded by many others, none of which complained of any problems. Some help would be greatly appreciated!! Thanks!
Angel ♥
Edit: Excuse my mistake, that should say Sims 4 CAS Demo (what a klutz lol)

The CC you downloaded was the sims 4 base game. CC for base game is not compatible with CAS Demo. Go to simnationblog.co.uk for CAS demo CC. Don't put CAS demo CC into the base game because same thing will happen. I'm also getting Sims 4 soon but not for Xmas, I'm getting it for my b-day (Monday).
BTW to change the thread title just click thread tools next to where it says watch thread.
I hope this solves your problem.

Lol cool glitch, imagine her in the actual game.

Awesome!! Thanks a bunch

Happy to help! I s your game fixed now?