Yes, that diagram at the end is correct. However, I’m assuming that you’ve chopped-up a network cable to wire this up, so you should take a very careful look at the colours of the wires as they are connected in the plug, and ensure that you are actually using the correct ones at the other end.
Yes.
Good thinking!
That’s correct. I have a a Raspberry Pi running Mosquitto and Node-Red. I have the Blynk plug-in for Node-Red installed, which gives me my Blynk connectivity as well as Alexa integration etc. You don’t need that if you are viewing the results in the serial monitor.
Yes…
Pete.