Well, I don't own the andthensome, so i dont know how to do the goat change. But, the people on here will need a little bit more information on the problems you are having. help them help you.
I've been working on the G.O.A.T. change for about a year now (it's hard to get perfect!) and I found that the more and more I do it, the more consistent it will get (duh). I usually am able to do it perfectly squared, and it doesn't matter as much anymore how the card is angled. It's just a nack that you have to develop, but once you have it, the change isn't nearly as daunting. Just keep working on it, and you will eventually have it down pat.