Sounds like you are making good progress now that the cat has lost his taste for plane parts

I had my battery wrapped tight eonough that there was a little movement to reduce shock but not loose that it would slid out easy. After you balance your plane you could take a strip of velcro and secure it in place. make sure to put some foam around your fuel tank to cut down on the bubbles. make sure the throttle pushrod doesn't bind though.