Alright! I can answer all of these except the first question about Capitals ranking.
Quitting or surrendering will give you the place that your AI is in when it finishes - so if your AI wins the game after you leave, you will be granted a win. It's where your AI places. No difference between quitting and surrendering. If you are the first to quit/surrender, your AI could still not be the first to lose so you could get a better score than losing first.