used mail-in-a-box, namecheap and hetzner
hetzner wants you to have paid 1 bill before they'll unblock outbound smtp ports
mail-in-a-box expects you have to a domain like foo.bar and host the email UI under box.foo.bar
to add the glue records to namecheap you have to specify the FULL domain i.e
ns1.box.mhyl.me
set namecheap to use the nameserver
drill ns me. to find the nameservers for your TLD
drill ns @b2.nic.me mhyl.me query a nameserver to check on your domain