You're over the first hurdle, hopefully his BAT will come back okay. I can't tell you how happy I am that you are in this all the way for Max, I didn't think you would be able to return him.
Please try to remain positive and enjoy Max, although I know it is hard to do when you are so worried and then see him have one of the seizures. Hopefully he will keep you entertained while you wait for the next results. He is so precious and you really are blessed to have him and be able to give him the help he needs.