Nessus file/directory Auditing

[k41zen at live.co.uk (k41zen)]

All,

Anyone got any info on how the Nessus Content Auditing element of Nessus works? It claims to check document keywords 
such as "TOP SECRET" or "CONFIDENTIAL" and I'm curious as to how it does this.

On top of this, I'm looking for a tool that could login to an SMB share and report back on files that are prefixed with 
something specific. Is this possible with Nessus?

Finally I'm also looking to scan an SMB share, searching for directories and sub-directories called something specific 
and then need to be able to check the perms on these to report back when a specific group which should be denied access 
is missing. Is this possible with Nessus?

Regards,

Jason