Would this not be best asked at vbulletin support if your asking a blog support question? Your viewing your site like so right
http://www.domain.com/forums/blog.php
That type of url is not photopost in any manner so as previously instructed by me in my previous posts your best thing is to view your that specific page and look at your image path error to see where its looking for those images. Do the images exist where your telling vbulletin they are suppose to be at. The problem with relative urls and photopost is only merely a matter of using relative paths and trying to show images over another directory that they exist. One of the reasons i always tell people when they ask for support place a url here for us to look at.