I'm now using W5100 Ethernet, this is what I have on startup:
0;255;3;0;9;Starting gateway (R-NGA-, 2.0.0-beta)
0;255;3;0;9;Init complete, id=0, parent=0, distance=0
0;255;3;0;9;Attempting MQTT connection...
0;255;3;0;9;MQTT connected
With the following request I was able control my 1st relay:
mygateway1-in/0/1/1/0/2 , value is either 0 or 1
Seems to be working!