External .as, adding scroll bar

Newbie, First let me say I’m looking for direction, make my project work, and to learn. I would have no problems making the scroll bar inside flash, however to do it in an external file and the code I’m using. I’m totally lost. My project is a scrollable help box inside a flash file.

I call the function with this code from an external AS file:

private function onHelp():Void {
		var obj=m_popupWnd.getValue();

			GlobalCs.help("Help Menu","<span class='bodySmall'>  Some lines of text goes here</span>",Style.m_cssStyles,"","",_global.cardRoot);

This is my GlobalCs.as file:

class GlobalCs
	static public function help(strTitle:String, strText:String, cssStyle:TextField.StyleSheet,
		strType:String, owner:MovieClip):MovieClip
		var wnd:MovieClip = Pseudo.PseudoHelp.alert(strTitle, strText, cssStyle, strType, null, owner, "CardAlert");
		var nW:Number = Math.min(Stage.width, owner.getW() ? owner.getW() : owner._width); //left positionscreen 
		var nH:Number = Math.min(Stage.height, owner.getH() ? owner.getH() : owner._height); //screen vertical position
		wnd._x = Math.round((nW - wnd.getW()) / 2); //screen right position
		wnd._y = Math.round((nH - wnd.getH()) / 2); //screen position bottom
		return wnd;

and this is my PseudoHelp.as file:

class Pseudo.PseudoHelp extends Pseudo.PseudoWindow
	static public function alert(strTitle:String, strText:String, cssStyle:TextField.StyleSheet,
		strType:String, null, owner:MovieClip, strClass:String):MovieClip
		var win:MovieClip = createWindow(owner, "mcAlert" + m_nCount, strTitle, "modal", false, strClass); 
		return win;

The above code will draw a help box and allow me to have text within a draggable box, but I need to make it a srcoll bar to enter more text than can display at one time in a browser window.

I appreciate all posts on direction, and very much understand that people are giving up their time to help.