Document Class not work when I shift my MovieClip to 2nd Frame.

Question

Hello,
All my content is at 1st frame of my FLA file...and I'm using Document Class... When I try to shift my content to 2nd frame, so I can use 1st frame for preloader.. but its not working...
This is my document class... Basically at 1st frame I'm loading external jpg image to a MovieClip..
Is it possible, I can **** my MovieClip and other content to 2nd frame of the timeline... ??? and Document Class work???
Thanks...
package com.ahmad.bg
     //import all classes
     import caurina.transitions.Tweener;
     import flash.display.Loader;
     import flash.display.MovieClip;
     import flash.display.Sprite;
     import flash.display.StageAlign;
     import flash.display.StageDisplayState;
     import flash.display.StageScaleMode;
     import flash.events.Event;
     import flash.events.MouseEvent;
     import flash.net.URLRequest;
     public class MainClass extends MovieClip
          //create variables
          private var loader:Loader;
          private static const IMAGE_PATH:String = "bgs/bg.jpg";         
          public function MainClass() {
               stage.align = StageAlign.TOP_LEFT;
               stage.scaleMode = StageScaleMode.NO_SCALE;              
               stage.addEventListener(Event.RESIZE, stageResize);         
               //load external image
               loader = new Loader();
               loader.load(new URLRequest(IMAGE_PATH));
               loader.contentLoaderInfo.addEventListener(Event.COMPLETE, showImage);
               pic.addChild(loader);    
          private function showImage(e:Event):void
               try {                             
                    e.target.content.alpha = 1;
                    Tweener.addTween(e.target.content, { alpha:1, time:1, transition:"easeOutSine" } );                   
                    e.target.content.smoothing = true;                             
               } catch (e:Error) { };
               stageResize();
          private function stageResize(e:Event=null):void
               pic.x = 0;
               pic.y = 0;
               pic.scaleX = pic.scaleY = 1;              
               if ((stage.stageHeight / stage.stageWidth) < pic.height / pic.width) {
                    pic.width = stage.stageWidth;
                    pic.scaleY = pic.scaleX;
               } else {
                    pic.height = stage.stageHeight;                   
                    pic.scaleX = pic.scaleY;
               pic.x = stage.stageWidth / 2 - pic.width / 2;
               pic.y = stage.stageHeight / 2 - pic.height / 2;         
               bottomNav.x = Math.floor(stage.stageWidth / 2 - bottomNav.width / 2);
               bottomNav.y = Math.floor(stage.stageHeight - bottomNav.height - 0);

Answer 1

If you have code in your main class that references specific movieclips on the stage, they have to be on every frame you plan on using.
If you have a movieclip named "pic" on frame 2, but you are referencing it right away in the main class, which starts on frame 1, then it is looking for a movieclip that does not exist until you move it to frame 2