Take a look on the Roots Google Group, here, they have a lot of info there and plenty of activity.
The Roots theme works slightly differently to many ‘conventional’ WP themes in that it makes heavy use of the get_template_part function to ‘stitch’ together different modular sections to form each page on your site.
I’ve always been a bit surprised that more themes aren’t structured like this but I know quite a few peeps have trouble getting their head round it because they are used to a different way. You have to think about building your site in a modular way and then stitching it together, it’s cool when you get used to it!