Rhino does not drag objects when mouse events are sent from plugin

We are sending mouse events from a C# plugin to the rhino application. But we can not make rhino to drag objects when we send mouse down and subsequent mouse move events from our plugin. Everything else like selecting and deselecting works and it is visible that the cursor moves on the object so it is not likely about a mouse location problem. Here is how we are sending the mouse events to the application:

    void sendMouseMessage(PureWebMouseEventArgs mouseEvent)
        int X = (int)mouseEvent.X;
        int Y = (int)mouseEvent.Y;

        setClientViewMousePosition(X, Y);

        IntPtr lParam = (IntPtr)((Y << 16) | X);
        IntPtr wParam = IntPtr.Zero;
        uint mouseEventType = convertMouseEventToInt(mouseEvent.EventType);
        SendMessage(Rhino.RhinoDoc.ActiveDoc.Views.ActiveView.Handle, mouseEventType, wParam, lParam);

If I understand correctly, you are trying to implement the object dragging that can occur when no command is running? If so, then object dragging uses, as you suspect, WM_LBUTTONDOWN, WM_MOUSEMOVE, and WM_LBUTTONUP messages to deal with object dragging.

So, do you there some plug-in code that I can run?