I love the mobile view of the Spacious Theme and use it in tandem with the Mobile Smart plugin for several sites that have other themes for desktop, especially non-responsive legacy themes like Kubrick. Unfortunately, recent updates to Spacious have messed up the mobile settings I was using. So disruptive have the updates been, that I’ve had to go back and reinstall Spacious 1.1.4.
To discourage the theme from being updated again, either by myself or someone else, I’ve changed the version number in the Spacious style.css file to 999999. Perhaps there are other ways to get WordPress.org to not send theme and plugin update notifications, but this little trick seems to work. Easy too.