Questions about disabling Magic Mouse scrolling in Chrome

I'm an absolute newbie when it comes to BTT, but I want to learn.

Question 1:

I tried using this option:


for Chrome, and it works, except when I flick up or down, it still scrolls as my finger comes up off the mouse. Which unfortunately I seem to do far too often. Is there something else I need to do?

Question 2:

What I'd really like to do is disable scrolling in Chrome only when on a specific subdomain,

I doubt there's that kind of granularity, but is there an easy way to be able to toggle scrolling in Chrome, say with a shortcut key or something?