Question about Game Play Screen tutorial: Complete Guide to Torque X

Hey guys, hopefully I have a rather simple question about page 339 - 340 of John's book, about creating a Game Play Screen. Here is the code, I've commented the changes I made for it to work:

public class GuiPlay:GUISceneview,IGUIScreen
{
    public GuiPlay()
    {
        //create the Style for our play screen
        //GUIStyle playStyle = new GUIStyle();
        //playStyle.Anchor=AnchorFlags.All; // this as I understand is not valid anymore 
        GUIControl playStyle = new GUIControl(); //these are the lines I replaced it with
        playStyle.HorizSizing = HorizSizing.Center;//these are the lines I replaced it with
        playStyle.VertSizing = VertSizing.Center;//these are the lines I replaced it with


        // set some info for this control
        Name = "GuiPlay";
        Style = playStyle; ;//this now gives me an error (cannot implicitely convert)
        Size= new SizeF 800,600); // replaced SizeF with Vector2. 
     }
}

So my question is, do I even need the GUIStyle anymore, and if so, what further changes do you think I should make to the code for creating the Game Play Screen?

Thanks for any help!