how to pause

gistfile1.as

var pauseGroup:PauseGroup;
var paused:Boolean = false;

public override function create():void {
  //your normal create
  pauseGroup = new PauseGroup();
}

public override function update():void {
  if(FlxG.keys.justPressed(MY_PAUSE_BUTTON)) {
    paused = !paused;
  }
  if(!paused) {
    updateLogic();
    super.update();
  } else {
    pauseGroup.update();
  }
}

public override function draw():void {
  super.draw();
  if(paused) pauseGroup.draw();
}

private function updateLogic():void {
  //Your update goes here
}