In regards to the pictures, most often they are hosted by the poster, or just linked to from somewhere else on the net. People tend to delete these pictures which is why they don't work.
As for the bad links in the forum, we had a major overhaul a few months ago and all the links get messed up. This thread explains what you can do
http://www.vwdiesel.net/forum/index.php?topic=19684If you do find a post with a bad link, click the "report to moderator" button and write in the comment section that there is a bad link. That way one of us moderators will fix it.