There are two presentation messages in the output. One is from the gateway presenting itself as node 0. One is from node 3 presenting child 10 as sensor type 5. There is no presentation of node 3 itself. Until a node is registered at the gateway it can't send any set/req messages. Registration happens after presentation is finished. In mysensors 2.0 registration is done after setup is called. In mysensors development branch setup is done after registration.