wr1 drayton wireless thermostat

I have a new British Gas WR1 wireless thermostat to replace my Honeywell direct wired thermostat. It has 4 wires Black, Brown, Grey and Earth. Im really struggling to get it working. I have pictured the honeywell. Which wires go where on the WR1 it has 6 terminals N, L, 1, 2, 3, 4 and no...