Did you use something simialar to the following program to test it...
Code:
program HelloWorld;

{$APPTYPE CONSOLE}

{%DelphiDotNetAssemblyCompiler '$(SystemRoot)\microsoft.net\framework\v1.1.4322\System.dll'}
{%DelphiDotNetAssemblyCompiler '$(SystemRoot)\microsoft.net\framework\v1.1.4322\System.Data.dll'}
{%DelphiDotNetAssemblyCompiler '$(SystemRoot)\microsoft.net\framework\v1.1.4322\System.Windows.Forms.dll'}
{%DelphiDotNetAssemblyCompiler '..\..\bin\delphi 2005\Irrlicht.NET.dll'}// You will probably have to change this path.


uses
  System.Windows.Forms,
  Irrlicht,
  Irrlicht.Video,
  Irrlicht.Core,
  Irrlicht.Scene;

var
  device : IrrlichtDevice;
  texSydney, texWall, texLogo : ITexture;
  mesh : Irrlicht.Scene.IAnimatedMesh;
  cam : ICameraSceneNode;
  node : ISceneNode;
  fps : integer;
begin
  // start up the engine
  device := IrrlichtDevice.Create(DriverType.OPENGL);

  device.ResizeAble := true;
  device.WindowCaption := 'Irrlicht.NET Delphi.NET example 01 - Hello World';

  // load some textures 

  texSydney := device.VideoDriver.GetTexture('..\..\media\sydney.bmp');
  texWall := device.VideoDriver.GetTexture('..\..\media\wall.bmp');
  texLogo := device.VideoDriver.GetTexture('..\..\media\irrlichtlogoaligned.jpg');

  // load the animated mesh of sydney

  mesh := device.SceneManager.GetMesh('..\..\media\sydney.md2');

  if (mesh = nil) then
  begin
    System.Windows.Forms.MessageBox.Show(
      'Could not load mesh ..\..\media\sydney.md2, exiting.',
      'Problem starting program');
    exit;
  end;

  // add a camera, a test scene node and the animated mesh to the scene	

  cam := device.SceneManager.AddCameraSceneNodeFPS(nil, 100, 100, -1);
  cam.Position := Vector3D.Create(20,0,-50);


  node := device.SceneManager.AddTestSceneNode(15, nil, -1, Vector3D.Create(30,-15,0));
  node.SetMaterialTexture(0, texWall);

  node := device.SceneManager.AddAnimatedMeshSceneNode(mesh, nil, -1);
  node.SetMaterialTexture(0, texSydney);
  node.SetMaterialFlag(MaterialFlag.LIGHTING, false);

  // make cursor invisible
  device.CursorControl.Visible := false;

  // start drawing loop

  fps := 0;

  while( device.Run ) do
  begin
    if (device.WindowActive) then
    begin
      device.VideoDriver.BeginScene( true, true, Color.Create( 0, 100, 100, 100 ) );

      device.SceneManager.DrawAll();
				
      // draw the logo
      device.VideoDriver.Draw2DImage(
        texLogo, Position2D.Create( 10, 10 ),
        Rect.Create( 0,0,88,31 ),
        Rect.Create( Position2D.Create( 0, 0 ),device.VideoDriver.ScreenSize),
        Color.Create($ffffff), false);

      device.VideoDriver.EndScene();

      if &#40;fps <> device.VideoDriver.FPS&#41; then
      begin
        fps &#58;= device.VideoDriver.FPS;
        device.WindowCaption &#58;= 'Irrlicht.NET Delphi.NET example 01 - Hello World &#91;'+ device.VideoDriver.Name + '&#93; fps&#58;' + fps.ToString;
      end;
    end;
  end; // end drawing-loop
end.
I can confirm that the problem occurs in Delphi 8 ( with all the patches ) as well (. I have sent the assembly to Borland in the hope that it will help them fix the problem.