[callme]

package
{
 
	import flash.display.Sprite;
	import flash.events.Event;
	/*
	import flash.display.Loader;
	import flash.net.URLRequest;
	import flash.text.TextField;
	import vk.APIConnection;
	import vk.api.serialization.json.JSON;
	*/
	/**
	 * ...
	 * @author Volodin Alexandr Sergeevich
	 */
	public class Main extends Sprite 
	{
 
		public function Main() 
		{
			if (stage) init();
			else addEventListener(Event.ADDED_TO_STAGE, init);
		}
 
		/*
		public var flashVars:Object = stage.loaderInfo.parameters as Object;
		public var VKAPI:APIConnection = new APIConnection(flashVars);
		public static var avatar:String = new String;
 
		private var txt:TextField;
		*/
 
		private function init(e:Event = null):void 
		{
			removeEventListener(Event.ADDED_TO_STAGE, init);
			// entry point
 
			addChild(new Profile); // добавил класс в Main
 
			/*
			txt = new TextField();
			txt.width = 800;
			txt.height = 600;
			txt.wordWrap = true;
			txt.appendText("> flashVars: " + JSON.encode(flashVars) + "\n\n");
			addChild(txt);
 
			VKAPI.api(
				"users.get", { user_ids:flashVars['viewer_id'], fields:"photo_50", name_case:"nom" }, usersGetSuccess, usersGetError
			);
			*/
		}
 
		/*
		public function usersGetSuccess(data:Object):void
		{
			txt.appendText("> usersGet: " + JSON.encode(data) + "\n\n");
			avatar = data[0].photo_50;
 
			txt.appendText("> avatar: " + avatar + "\n\n");
 
			var loader:Loader = new Loader();
			loader.load(new URLRequest(avatar));
			loader.x = 100;
			loader.y = 100;
			addChild(loader);
		}
 
		public function usersGetError(data:Object):void
		{
			txt.appendText("> usersGet: error: " + JSON.encode(data) + "\n\n");
		}
		*/
	}
 
}

package  
{
 
	import flash.display.Loader;
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.net.URLRequest;
	import flash.text.TextField;
	import vk.APIConnection;
	import vk.api.serialization.json.JSON;
 
	/**
	 * ...
	 * @author Volodin Alexandr Sergeevich
	 */
	public class Profile extends Sprite
	{
 
		public var flashVars:Object;
		public var VKAPI:APIConnection;
		public static var avatar:String = new String;
 
		private var txt:TextField;
 
		public function Profile() 
		{
			txt = new TextField();
			txt.width = 800;
			txt.height = 600;
			txt.wordWrap = true;
			addChild(txt);
 
			addEventListener(Event.ADDED_TO_STAGE, addedToStage);
		}
 
		private function addedToStage(e:Event):void 
		{
			flashVars = stage.loaderInfo.parameters as Object;
			VKAPI = new APIConnection(flashVars);
 
			txt.appendText("> flashVars: " + JSON.encode(flashVars) + "\n\n");
 
			VKAPI.api(
				"users.get", { user_ids:flashVars['viewer_id'], fields:"photo_50", name_case:"nom" }, usersGetSuccess, usersGetError
			);
		}
 
		public function usersGetSuccess(data:Object):void
		{
			txt.appendText("> usersGet: " + JSON.encode(data) + "\n\n");
			avatar = data[0].photo_50;
 
			txt.appendText("> avatar: " + avatar + "\n\n");
 
			var loader:Loader = new Loader();
			loader.load(new URLRequest(avatar));
			loader.x = 100;
			loader.y = 100;
			addChild(loader);
		}
 
		public function usersGetError(data:Object):void
		{
			txt.appendText("> usersGet: error: " + JSON.encode(data) + "\n\n");
		}
 
	}
 
}

Добавлено через 1 минуту
Напишите к каким выводам пришли после прочтения моего кода.