http://www.thinkbroadband.com/ip.html shows your IP if you browse out from that connection.

Can you ping or traceroute to the actual IP (as above) and to the no-ip.org IP mapped to the actual IP. May need WAN side ping response enabling.

Also check router firewall logs for dumped incoming connection (or otherwise).

well spotted!

The DNS entry had been trashed, so I reset it to the gateway and Robert is my Dads' brother....

Don't know quite why the entry got trashed (it had been cleared to a null field) or why it didn't work when the Technicolour router was in use (when the settings were derived using DHCP) I really can't understand, but on a very brief test from my mobile, it now seems to be delivering the web page I'd expect.

Many thanks!

Edited by deleted (Wed 06-Mar-13 20:22:51)

That's good to hear! Glad you sorted it out