Unable to get ESP8266 wifi working

That is strange. So that's exactly the same wiring you had when running the version checking code?

You do seem to have some saved code though - could you try typing reset() followed by save() on the left-hand side, and then trying upload again?

I guess it's possible that the ESP8266 was already powered up by the saved code, and the combination of turning it off for a split second for the reset and then powering it back on caused some kind of problems.

Sorry to hear about your Pico - what revision is the PCB on it (it should be printed on the back I think)? The later ones have a self-resetting fuse so even if you short ground and VCC you're very unlikely to cause any damage.

One other thing - could you add wifi.at.debug() right after your existing code - so:

digitalWrite(B9,1);
Serial2.setup(115200, { rx: A3, tx: A2 });
var wifi = require("ESP8266WiFi_0v25").connect(Seri­al2, function(err){
  if (err) throw err;
  console.log("Connecting to WiFi");
  wifi.connect("MY_LAN", "PASSWORD", function(err){
    if (err) throw err;
    console.log("Connected");
    require("http").get("http://www.pur3.co.­uk/hello.txt", function(res){
      console.log("Response: ", res);
      res.on('data', function(d){ console.log("--->"+d); });
    });
  });
});
wifi.at.debug();

and post up what gets printed out? It might help I guess.