Limit Website Catalog to Certain Subdirectories?

[Andrew]

Is there a way to create a catalog that returns the vpath property of
documents contained in limited parts of a site's virtual root without
cataloging the entire web site?

Background: I manage a website with hundreds of thousands of pages
across thousands of subdirectories under the site's virtual root. I
need to maintain several publicly available websearches that use
indexing service to return web addresses (AKA the vpath) for only a
very limited number of those documents.

Cataloging the entire site takes up valuable CPU, memory and hard
drive resources. So I am not interested in just using the ciScope
parameter in the .idq file to limit the returned set of documents. I
want to limit the size and contents of the catalog itself, but I must
be able to retrieve the vpath property that only becomes available
when you add a website to the tracking. The parts of the site I wish
to catalog do not have their own virtual root, nor do I want to make
them into virtual roots. They are and should remain subdirectories of
the site's main virtual root.

I've spent many days hunting the MSDN and various textbooks for
details on how exactly IIS and IS can be configured carefully, but
without finding any reference to what seems to me to be a pretty
obvious need for webmasters. How do you limit a catalog to just parts
of a website and still get the vpath property returned?

If you find the above an easy question, here are some *bonus*
questions that I don't need necessarily need answered but that I find
baffling:

1. Why do I get an error popup headlined "Invalid Directory," that
reads "The request is not supported," when I click a virtual root
directory in my catalog and select "No" under "Include in index?"

2. What is the relationship between going into IIS, selecting a
directory and checking off "Index this resource" vs. going into
explorer, selecting that same directory and selecting properties >
advanced and checking off "For fast searching, allow Indexing Service
to index this folder?" Toggling one checkbox seems to have no effect
on the status of the other.

3. How do I get a list of the locations of every virtual root/virtual
directory created under my website?

4. Why do some virtual directories seem to appear when I choose to
track a site, but not others?

5. How do I view or retrieve the entire contents of a catalog so that
it lists every field and every record in a grid? How do I sort those
same results on different fields?

[Marc J. Cawood]

Have you tried making the search catalog in the Index Server MMC Snap-
In instead of in IIS? There you can add each directory you want
seperately, each with a given alias. In my experience it's trivial to
get from the Directory Path to the VPath with a new lines of ASP.