Keyword link replacement feature - Help please

Is there a document somewhere that explains the Keyword Link Replacement feature in VBSEO?
I can't find info about it and can't see any mention of it in our VBSEO CP (VBSEO 3.3.2)

What I would like to do is to replace certain keywords in our forum with text hyperlinks that point to the relevant items in our online shop.
I believe that's what the Keyword link replacement feature is for, is that right?

Also.... is it possible that I can set it to do this rewrite only for guests? Ideally, that would display the links to crawlers, but not annoy our regular registered users.

thanks in advance,
James

Please check keyword link replacements