The links to the resources should explain the basic steps. Your content won’t change if you update….of course you should back everything up just in case it doesn’t for any reason. If you haven’t made any changes to your css or any other files then I’d just delete the old theme and install the newer version. So the main question is, Have you made any changes to your css file, or any other file of the theme? If not then go ahead an update. Also, you should be able to save your Genesis theme options settings in an export file.
An automatic update would be good, but I haven’t seen a way to do this since it’s not really offered for child themes…..but it does exist for the Framework (Genesis). Most people wouldn’t want an automatic update for child themes since they make customizations to their css file, and an automatic update would completely overwrite any changes they’ve made. That’s the reason why it doesn’t exist for Genesis Child themes.
I’m wondering if there’s a way to do it with WP Multisite. I want to say there is, but I can’t really comment since I haven’t used it just yet, but I think that’s what it does.
Let me know if that was helpful.
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