Node-red-contrib-blynk-websockets for dummies

I’ve successfully installed Blynk local server + Node-Red + Node-red-contrib-blynk-websockets.
I have uploaded simple example to ESP8266 NodeMCU. There are built-in blue LED on D4.
I have simple IOS dashboard with 2 buttons

  1. D4 (for NodeMCU connectivity test).
  2. V0 (for NodeRed test)
    Test button 1) works good, blue LED lights ON/OFF
    Test button 2) I’m trying to get any test feedback in NodeRed:

    How get any message in NodeRed, about pin V0 state changing?

I’ve got this result from debug form write node:

msg.payload : string[1]
msg.payload : string[1]