Wow, impressive work! Really nice instructions. I think I will try this.

@mfalkvidd Awesome! I will check the debug logs from my node and gateway this evening.

If you would like to try something simple and you happen to use a serial gateway. You can just write to the USB port of the GW.
For example like this:
$ echo -n "1;1;1;0;24;SP=20.0\n" > /dev/ttyUSB0
See https://www.mysensors.org/download/serial_api_20 for API
node-id;child-sensor-id;command;ack;type;payload\n
The sketch for the receiving node need to "receive" V_VAR1 in this case.