Hi.
I don't have any experience with dynamic dns, but I'll throw my two bob in.
I assume any dynamic DNS stuff would have to be done via the admin console, although I could be wrong.
Log into your server as admin.
Select option 2, "configure this server".
Select "next" through each option to leave them unchanged until you get to "Select dynamic DNS service".
You should find what you need there.
Hope this helps.
JoshAU