Hi Nathan. Congrats on the launch of the page builder!
I was looking through the css of the 'abbey' page https://demo.ck.page/abbey and noticed a problem: the spinner doesn't show correctly on the submit button. More specifically, it does show, but the word 'Subscribe' is over the top when it should be hidden, so you can't see the spinner properly. The problem is an easy fix, it's just a small misalignment between the css selector and html structure :)