I have spent a few hours reading the docs, and I am sure 
that I am missing something.

I want to be able to cache a forum.  The problem that I am 
having is that many forum posts include an img tag that 
refer to an external domain.  It caches the posts but 
doesn't cache the images off-site.  I don't need any links 
to be followed to external sites, just the images referred 
to on the site.

How can I get this to work, for example 
on <http://www.tbreak.com/forums/forumdisplay.php?f=21>?
Among a ton of other things, I have tried:
  - (scan rules) setting the scan rule to "*"
  - (limits) maxiumum external depth 1
  - (links) get non-html files related to a link

I really appreciate any help on the matter!