Problema na definição de classes

[tassiocaique]

Olá pessoal, tudo bem ?

Bem, estou com um problema na definição de uma classe. O compilador apresenta os seguintes erros:

...\Welcome.as(23): col: 4 Error: The private attribute may be used only on class property definitions.

...\Welcome.as(30): col: 4 Error: The public attribute can only be used inside a package.

...\Welcome.as(57): col: 4 Error: The public attribute can only be used inside a package.

O código de definição segue abaixo:

package screens 
{
    import starling.display.Button;
    import starling.display.Image;
    import starling.display.Sprite;
    import starling.events.Event;
    
    public class Welcome extends Sprite 
    {
        private var bg:Image;
        private var title:Image;
        private var hero:Image;
        
        private var playBtn:Button;
        private var aboutBtn:Button;
        
        
        public function Welcome() 
        {
            //super();
            this.addEventListener(starling.events.Event.ADDED_TO_STAGE, onAddedToStage);
            
            private function onAddedToStage(event:Event):void 
            {
                trace ("WelcomeScreen to initialized");
                
                drawScreen();
            }
            
            public function drawScreen():void
            {
                bg = new Image(Assets.getTexture("BgWelcome"));
                this.addChild(bg);
                
                title = new Image(Assets.getTexture("WelcomeTitle"));
                title.x = 440;
                title.y = 20;
                this.addChild(title);
                
                hero = new Image(Assets.getTexture("WelcomeHero"));
                this.addChild(hero);
                hero.x = -hero.width;
                hero.y = 100;
                
                playBtn  = new Button(Assets.getTexture("WelcomePlayBtn"));
                this.addChild(playBtn);
                playBtn.x = 500;
                playBtn.y = 260;
                
                aboutBtn = new Button(Assets.getTexture("WelcomeAboutBtn"));
                this.addChild(aboutBtn);
                aboutBtn.x = 410;
                aboutBtn.y = 380;
                                
            }
            
            public function initialize():void        
            {
                this.visible = true;                
                hero.x = -hero.width;
                hero.y = 100;
            }
        }
    }
}

Eu uso a última versão do FlashDevelop, AIR 3.2 e Flash Debug Player 11.2 ...

Qual pode ser o problema?

Desde já, obrigado