[Milhouse]

I'm saying it works on build 'devel-20140714003359-r18727-g5a42541' - is this the #0714 build? Any later version doesn't work.

Thanks for the clarification, yes that's the original #0714 release. It's not obvious which additional PR in #0714b would be responsible for introducing this problem.

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.

3 - trough Openelec settings connect to your access point. Enter wpa passphrase, etc;

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

6 - now, try to enter a gateway ip address

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

At least you are able to see and select the Gateway field - the previously mentioned PRs (4919/4971/5025 etc.) would not even show you certain fields so I think it's safe to rule them out.