I can probably help you with this, but the guys at Naim support are really good at it and will be able to sort it for you. If you can't manage to follow their instructions, they can also do a remote login and actually set it up for you. Get on the phone to Naim support, you'll probably get to talk to Phil Harris.
Regarding choice of NAS, a Synology, QNAP or Netgear Readynas, all with Western Digital Red drives would be my choice. They are all pretty well tried and tested. An SSD drive might be quieter than HDD, although the noise from my Synology is mainly from the fan, not the drive. Not too much of a problem if you can keep the thing away from the listening room.