[Xymon] xymonproxy SetUp Help Requested

I have an xymon client for a NAS but the NAS is connected via another xymon client and is not reachable from the xymon server. How would I set this up in the xymon server configuration - does it need a hosts.cfg entry and if so, what would it look like? On the client, do I give it the address of the xymon client running xymonproxy or the actual server?

Regards,

Nick Pettefar