For help setting up your DNS server using iDNS, the easiest documentation to follow would be Apple's own because iDNS uses the same interface as Server Admin on Mac OS X Server. There will hopefully be a FAQ coming soon, but for the mean time, please use Chapter 3 of Apple's documentation:
If you still cant find what your looking for and need help, you can get in touch with me using the "Contact" tab above.
How It Works
iDNS uses the built-in DNS capabilities of Mac OS X. The DNS server Mac OS X uses is called BIND, the de facto standard open source UNIX DNS server that is very stable. This same tool is used in Apple's very own Mac OS X Server. Obviously, Apple have not included the software needed to configure the DNS server in Mac OS X Client because it would give people one less reason to buy Mac OS X Server.
From the iDNS application menu, choose Unregister iDNS. This will revert your DNS settings back to your computers original settings and will allow you to register iDNS on another Mac. Once you have done this, you can delete the iDNS application file.
I can't register iDNS
If you are having trouble registering iDNS, please try to use the online tool to fix your license. You must have a MacServe account for this to be available to you. There are some cases in which invalid serials are being generated. Also, if PayPal's record of your name includes a middle name or any non-standard characters (e.g. Japanese characters or accents), your serial may be invalid. If this is affecting you, the online tool should fix this for you. If you still have problems after using this tool, please contact me and I will issue you with a new serial.