I've tried to load my forum with port 8000 (http://*.rhcloud.com:8000) and then in category permissions groups are shown properly. I'll use http://myhost.rhcloud.com:8000 when want to set category permissions.
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.