[slack3r]

1 - disable dhcp on your router;

Presumably this step is necessary, what happens if DHCP is still running on your network, can you then enter the gateway? If so that would seem very odd.

Yes, step 1 is mandatory.
If DHCP is running i can make a static connection, but I can not set more than one DNS server. I don't remember if i can edit gateway address (I had no reason to do it, I guess): I should test it again.

Unfortunately I don't have WiFi on my Pi but have been able to set a gateway for a wired connection.

Is there the issue? This evening I can test a wired connection.

I can get to this screen with my wired connection and build #0727.

Me too on the same build.

When I press ENTER on my remote in the Gateway field the IP address dialog box appears, but you're saying when you press ENTER nothing happens - no response?

I don't know how to say it in English, but pressing Enter I'm get back to 'IPV4' item on left column. Nothing else happens.