RasterImageViewer Control Load Error

I have exception on RasterImageViewer loding..

RasterImageViewer in UserControl(Name is "A")
UserControl "A" in UserControl(Name is "B")
UserControl "B" in Window

Exception is..

Message : NullReference exception
Source : Leadtools.Windows.Controls
TargetSite Void a(System.Object, System.windows.RoutedEventArgs)
StackTrace :
위치: Leadtools.Windows.Controls.BitmapSourceViewer.a(Object A_0, RoutedEventArgs A_1)
위치: System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
위치: System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
위치: System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
위치: System.Windows.UIElement.RaiseEvent(RoutedEventArgs e)
위치: System.Windows.BroadcastEventHelper.BroadcastEvent(DependencyObject root, RoutedEvent routedEvent)
위치: System.Windows.BroadcastEventHelper.BroadcastLoadedEvent(Object root)
위치: MS.Internal.LoadedOrUnloadedOperation.DoWork()
위치: System.Windows.Media.MediaContext.FireLoadedPendingCallbacks()
위치: System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks()
위치: System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget)
위치: System.Windows.Media.MediaContext.RenderMessageHandler(Object resizedCompositionTarget)
위치: System.Windows.Media.MediaContext.Resize(ICompositionTarget resizedCompositionTarget)
위치: System.Windows.Interop.HwndTarget.OnResize()
위치: System.Windows.Interop.HwndTarget.HandleMessage(Int32 msg, IntPtr wparam, IntPtr lparam)
위치: System.Windows.Interop.HwndSource.HwndTargetFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
위치: MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
위치: MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
위치: System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter)
위치: System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler)

The exception raise only this case..
I guess that RasterImageViewer did not created..

When using our DLLs in an application, our referenced DLLs must be deployed in the same folder that has the application's EXE, even if the EXE is referencing the DLLs through another DLL, and not directly.

Please note that our components can only be used to create an end-user application. This means if you are creating components that will be used by other programmers, you will need LEADTOOLS SDK licenses for each programmer who uses these components.