Originally Posted by SmoothJazz
Adding photos is kind of weird, first you have to upload your pictures you want in the gallery to an album in your profile, then copy the URL and use it to upload it into the group's gallery.
Actually, you don't have to mess around with URLs in order to add pictures to a group. Just open up your album, and below the pictures you'll notice a grey bar with a link that says "Add Pictures to a Group". Click on it, choose the pictures you want to add by clicking on them and finally select the target group from the pop-up menu. Even a singer could do it!