I use Analog which I was easily able to configure to put its output into a file named index_html, which I server via LocalFS. Works fine. LocalFS would work ok for webalizer too - it doesn't strip extensions. Only problem is, LocalFS doesn't prevent edits TTW like FSDV does - but you can enforce that by setting permissions (either on the filesystem so the zope process ownere cannot write to that directory, or in zope by configuring permissions on the LocalFS instance).
I've tried to serve webalizer files through Zope myself at some point, but I didn't really see the point. I could not find a way to customize webalizer to create output that would really "fit seamlessly" into the look and feel laid down by my design in Zope. After that it just felt wasteful to serve those files through Zope for basically no gain, so I set it up in Apache. jens