ADD a mouse and keyboard mover to a scrollpane

hi I have a working scroll pane script that i obtained online, and i need to add a mouse wheel and keyboard up and down to also move the content up and down can someone help me please and show me what to add where, or add it for me so that i can copy and paste it in to my action pane please.im not sure if there is any thing unnecessary in this code im putting as an example, because i got it off the internet.

my existing script looks like this :

scrolling = function () {

  var scrollHeight:Number = scrollTrack._height;

  var contentHeight:Number = contentMain._height;

  var scrollFaceHeight:Number = scrollFace._height;

  var maskHeight:Number = maskedView._height;

  var initPosition:Number = scrollFace._y=scrollTrack._y;

  var initContentPos:Number = contentMain._y;

  var finalContentPos:Number = maskHeight-contentHeight+initContentPos;

  var left:Number = scrollTrack._x;

  var top:Number = scrollTrack._y;

  var right:Number = scrollTrack._x;

  var bottom:Number = scrollTrack._height-scrollFaceHeight+scrollTrack._y;

  var dy:Number = 0;

  var speed:Number = 10;

  var moveVal:Number = (contentHeight-maskHeight)/(scrollHeight-scrollFaceHeight);

  scrollFace.onPress = function() {

  var currPos:Number = this._y;

  startDrag(this, false, left, top, right, bottom);

  this.onMouseMove = function() {

  dy = Math.abs(initPosition-this._y);

  contentMain._y = Math.round(dy*-1*moveVal+initContentPos);

  };

  };

  scrollFace.onMouseUp = function() {

  stopDrag();

  delete this.onMouseMove;

  };

  btnUp.onPress = function() {

  this.onEnterFrame = function() {

  if (contentMain._y+speed<maskedView._y) {

  if (scrollFace._y<=top) {

  scrollFace._y = top;

  } else {

  scrollFace._y -= speed/moveVal;

  }

  contentMain._y += speed;

  } else {

  scrollFace._y = top;

  contentMain._y = maskedView._y;

  delete this.onEnterFrame;

  }

  };

  };

  btnUp.onDragOut = function() {

  delete this.onEnterFrame;

  };

  btnUp.onRelease = function() {

  delete this.onEnterFrame;

  };

  btnDown.onPress = function() {

  this.onEnterFrame = function() {

  if (contentMain._y-speed>finalContentPos) {

  if (scrollFace._y>=bottom) {

  scrollFace._y = bottom;

  } else {

  scrollFace._y += speed/moveVal;

  }

  contentMain._y -= speed;

  } else {

  scrollFace._y = bottom;

  contentMain._y = finalContentPos;

  delete this.onEnterFrame;

  }

  };

  };

  btnDown.onRelease = function() {

  delete this.onEnterFrame;

  };

  btnDown.onDragOut = function() {

  delete this.onEnterFrame;

  };

  if (contentHeight<maskHeight) {

  scrollFace._visible = false;

  btnUp.enabled = false;

  btnDown.enabled = false;

  } else {

  scrollFace._visible = true;

  btnUp.enabled = true;

  btnDown.enabled = true;

  }

};

scrolling();