Configuring Norton Personal Firewall assistance requested

Here's one you may have seen before: from time to time, I get the
dreaded red "X" (or its equal with Opera or Mozilla) where an image
should be if Norton Personal Firewall is enabled; if I disable it, the
image is viewable. I know that a GENERAL site can be configured as a
trusted site, but what if a site has several levels/pages that are
accessed from the home page? How does one configure an entire site,
the various levels/threads (for a message board) included so that one
sees any image on any page?

It's been suggested elsewhere that I junk Norton and go with another
firewall. At the moment, that's not an option, so I need a reasonable
work-around for the short term. Thanks.