Thanks, that helped. I documented the steps for S2I here: https://github.com/appuio/nodebb-s2i
I've been playing around with a new template and when view posts on a topic, I've managed to get it to colour the user's name with the same colour as the selected group as per their profile.
Do you know how I can do this with the lastpost.tpl on category view? I've tried to do it the same way as I do with the post view, however when I look for the selectedGroup/selectedGroups array, I can't find it.
Thanks in advance.