DNS zone transfer

[binaryrogue]

I would like to allow zone transfer to a backup DNS server which is hosted by EditDNS. The IPSConfig box is currently now acting as the master and accepting DNS request from outside.

What else do I need to do besides adding the IP's "slave domain" where it says:
Allow zone transfers to these IPs (comma separated list) under the DNS tab for my zone?

For some reason it's not working. Are there any logs that I can look to see if the request being made from EditDNS? Do I need to modify any config files?