Controlling an open plan area
If your open plan living area maintains a constant temperature across all parts of it, the simplest way to control this is as a single zone on the App.
The Genius Radiator Valves can individually measure the temperature to keep all areas at comfortable temperature of your choice.
If one area heats differently to the rest
If one area has a considerable different temperature you can try setting a Hidden Valve Offset for that Genius Radiator Valve so that it will individually work harder/less hard than the others in the zone.
See this link for setting a Hidden Valve Offset