I dl a few cc dogs like scooby doo and dogmeat and whenever I go into CAS to create a family using them I get an error because I can't choose traits for my animals.

No traits show up for me to choose, yet I'm still forced to pick one or not continue. There is nothing showing up and I'm wondering if this is just my game or what.
I can't choose traits for animals I create either.

Sounds like you may have an old/conflicting mod installed, or not installed correctly.
Check the Game Help

I can make them but if I make a horse then it can't max out it's racing bar once it's in the game, it stays stuck at 4 no matter how much the horse runs.
Any horse I buy in game or adopt from the wild has no problems... just the ones I make.
It seems like the ep for the game is a bit buggy.

That sounds like a CC issue, actually. Easy answer is to try it with no CC and see if it works.

• Discussion - Sims 3 Game Problem
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