Ethernet Gateway connection to Raspberry Pi

[urbanus]

I have managed to get a working system by using Arduino Mega with the NRF24 (the one with the Aerial Connection) running the serial sketch - connected to a RPi2 running Domoticz and connected to the Arduino by USB.
This seems an expensive way to sort out a gateway so I will persevere with trying to find why I cannot get the other versions up and running but at least now I have a system - knitting will have to wait!!
Thanks for the help, much appreciated.