Error configuring my DNS

First, sorry my bad english, I'm Brazilian and not mastered the language.

I am a few days ago trying to solve the DNS problem on my server. I got a server in PhoenixNap company installed CWP without problems, but I am not able to configure my dns.

In Brazil for addresses ending in .com * must be registered in registro.br and it has a DNS checking tool in which you are returning me with error:

http://registro.br/cgi-bin/nicbr/dnscheck

In the above message is saying: "Time Exhausted"

In this environment I will have two sites, at the moment I am asking your help to set up only one in which I have custom nameservers, as you can see in the image:










I tried to bring much information, but if you need more information please let me know. I desperately need your help.