Hi,
I see this problem has occurred a few times before on this forum, I too am having the same problem, in that I try to install NOF Essentials, complete the registration details, and fail to receive a registration code I have emailed support the response directed me to the support centre so I placed a ticket there received a confirmation but still have had no response about the registration code.
Any advice would be greatly appreciated I know that the email address is valid as I have received the responses from support to the same address.