> I have mirrored a site and want to monitor it frequently 
> only for updates.  However, I want to grab those update 
> files into a separate directory while preserving the 
> original mirror so that I can do a comparison to see what 
> is new on the new files. 

You can check which files were updated by looking the log 
files (or with the former release, the hts-cache/new.txt 
file) ; but you can't really create new files in a 
different directory (also mainly because the engine will 
have to rescan the cached files to rebuild the link 
structure)