This seems to be too complicated than it has to be....
Here's what I do:
I replace {$postrow[$i]['Title']} in showflat.tmpl and showthreaded.tmpl with:
[]
<img src="{$config['images']}/{$postrow[$i]['Title']}.gif" />
[/]
Then all you have to do is upload files into your threads' image directory that are named the same as the titles you have set.
For example, if you have an image named newbie.gif that you want to use for newbies, then you put in newbie as a title.
This has worked for me since I started using threads with 6.2 all the way through 6.3 b1
