I don't believe there is a quick way to reset to stock settings. I think you're going to have to manually check and reset all of the registers yourself.
If you need a Nox manual (last time I checked www.buynox.com
was down) you can get one in the Manuals & Downloads section of www.icd-owners.com
If you have any questions about recommended settings just post up your questions and we'll get back to you.