BBC micro:bit save(); problems, again. and a question about BLE

I haven't used Espruino (or my micro:bit) for a while, I downloaded the latest (1v90) for the microbit and flashed it, however save(); either isnt working or has severely changed since 1v86. @Gordon helped me with this before.

This is the code i have:

function m() {
  show(0b1);
}
function onInit(){
  m();
}
save();

on 1v86 this is the output:

on 1v90 this is the output:

2 Things
1) I don't know why on 1v90 it thinks its 4200 bytes and on 1v86 it is just 3720...
2) If i power my microbit with 1v86 after running that code it displays the first led (correct) on 1v90, nothing happens.

Quick question about bluetooth / nRF, I noticed in changelog it has been changed, however I am unsure of how to change the broadcast name from "ESPRUINO Microbit" it just says

options is an object, which can contain:

{
name: "Hello" // The name of the device
showName: true/false // include full name, or nothing
discoverable: true/false // general discoverable, or limited - default is limited
interval: 600 // Advertising interval in msec, between 20 and 10000
}

And i dont really understand it..