FLASH Error #1009: 无法访问空对象引用的属性或方法。

网上下载有相册程序PPGallery.fla,这个相册是自动适应分辨率的,生成swf独立运行它没有问题, 现在问题是:我再做一个flash ,要在里面加载这个相册文件PPGallery.swf
不能加载,提示:
TypeError: Error #1009: 无法访问空对象引用的属性或方法。
at PPGallery/Initial3D()
at PPGallery()
-------------------------------------------
Initial3D()程序如下

public function Initial3D():void
{
// Align , scale Stage to full fill screen
stage.align = StageAlign.TOP_LEFT;
stage.scaleMode = StageScaleMode.NO_SCALE;
buttonMode = true;
// Reposition element if stage is resized
stage.addEventListener( Event.RESIZE, rePosition);

// Add Mouse Cursor
handMode = hand;
handDrag.visible = false;
Mouse.hide();
stage.addEventListener(MouseEvent.MOUSE_MOVE, mouseMove);
// Stretch preloader to fit stage dimension
preloaderEach.progressBar.width = preloaderEach.backPreloader.width = stage.stageWidth;
// Tempary remove components
removeChild(descBoard);
removeChild(preloaderFull);
removeChild(preloaderEach);
removeChild(fullDescription);
fullDescription.content.width = stage.stageWidth - 5;
fullDescription.back.width = stage.stageWidth;
fullDescription.content.autoSize = TextFieldAutoSize.LEFT;

// Viewport
viewport = new Viewport3D(stage.stageWidth, stage.stageHeight, true, true);
addChild(viewport);
addChild(hand);
addChild(handDrag);

// Camera 3D
camera.zoom = cameraZoom;
camera.y = 0;
camera.z = cameraZDefault;
camera.x = -stage.stageWidth;
// preloader
preloaderFull.x = stage.stageWidth / 2;
preloaderFull.y = stage.stageHeight / 2;
preloaderEach.x = 0;
preloaderEach.y = stage.stageHeight / 2;
// init Stylesheet
initStyleSheet();
}

handDrag
preloaderEach
fullDescriptio
camera
preloaderFull
....
不知道这么多的变量或属性你都有没有定义。所以不好说空对象到底是哪个，在几个关键点之间输出消息看看到底是缺少哪个变量引起的吧。

无法访问空对象引用的属性或方法 提示已经很清楚了 做断点去调试就清楚是哪里错了