[SOLVED]Drawing problems with C# and SdlDotNet

using System;
using System.Drawing;

using SdlDotNet;

namespace SDL_Test
{
	public class App
	{
		private bool done;
		private const int height = 480;
		private const int width = 640;
		private int xPos, yPos;
		private Surface screen;

		public App()
		{
			Events.KeyboardDown += new KeyboardEventHandler(this.KeyDown);
			Events.Quit += new QuitEventHandler(this.Quit);
			screen = Video.SetVideoModeWindow(width, height);
			Video.WindowCaption = "C# with SDL.NET";
			done = false;
			xPos = 100;
			yPos = 200;
		}

		private void KeyDown(object sender, KeyboardEventArgs e)
		{
			switch (e.Key)
			{
				case (Key.Escape):
				{
					done = true;
					break;
				}
				case (Key.Q):
				{
					done = true;
					break;
				}
			}
		}

		private void Quit(object sender, QuitEventArgs e)
		{
			done = true;
		}
		
		public void Run()
		{
			Surface background = new Surface("images/bg.bmp");
			Surface spaceship = new Surface("images/ship.jpg");
			spaceship.TransparentColor = System.Drawing.Color.Magenta;  // R = 255 G = 0 B = 255
			spaceship.Transparent = true;

			while (done == false)
			{
				while(Events.Poll())
				{
				}
				screen.Blit(background, new Rectangle(new Point(0,0), background.Size));
				screen.Blit(spaceship, new Rectangle(new Point(xPos,yPos), spaceship.Size));
				screen.Flip();
			}
		}

		public static void Main()
		{
			App mainApp = new App();
			mainApp.Run();
		}
	}
}