It's the filepath that you chose when you installed PHPRetro, it can't find where the images, css etc is stored. Re install and make sure you have the correct filepath.
Looks like you put a lot of effort into this thread and for that I'll thank you, but the thing is no one plays hamachi retro's no more, I would suggest tweaking this to show people how to portforward an IP.
I've put this idea forward in another thread before, but I'll post it here in hope that Rasta sees it.
Instead of paying to go up in ranks like less popular topsites, there should be an option to instead make your ranking stand out more, therefore I suggest this being in the form of increasing...