OK, so I’ve played around it some more and it seems that any replies to the original post won’t allow image uploads even though the image browse fields are there. I was wrong about the Group – it seems to be applicable to replying or commenting to a forum post.
Sorry, I’d also like to disable the “Whats New” post updates too. I know these are supposed to mimmick Facebook style status updates, but for some reason my members are posting there instead of on the comments. How can I disable this too?