What is the check to tame animals? I know its a Survival check but how do I determine difficulty? The main reason I'm asking is my wife wants to tame a Loth-Cat.

I would say it's possibly based on willpower. With some extra drawbacks depending on the type. I think the AoR ace book has more rules on it.

It is in Stay on Target. A hard Survival check upgraded x times where x is the creature's willpower. It takes about a week with advantages, triumphs, disadvantages, etc. changing the time required.