First off, great mod, Installed on my Test forum and am still tweaking it.
Second, I just wasted 45 minutes only to find out that the reason why the photos weren't appearing in my test ads (and not uploading) was due to the usergroup "minimum" restriction. Please post that one line explaining that the value must be set in order for them to appear in your installation instructions, as I would have preferred not to find the answer for that so deep into this thread.
Otherwise, the reason for the blank page for the others is that you simply need to follow the author's instructions for adding the link in your navbar. It requires that value for the page to display properly, otherwise you get the blank page. The install instructions are very clear and concise, and well done.
Again, don't take my comment negatively, I love your mod and am looking forward to implementing it. But adding that one bit of information could have saved me a bunch of time
Ian