C#

namespace MyWordAddin
{
    public partial class ThisAddIn
    {
        private ctlClock myUserControl;
        private Microsoft.Office.Tools.CustomTaskPane myCustomTaskPane;
        private int hour, min;
        private AddInUtilities utilities;

        protected override object RequestComAddInAutomationService()
        {
            if (utilities == null)
            {
                utilities = new AddInUtilities();
            }
            return utilities;
        }

        public int Min
        {
            get { return min; }
            set { min = value; }
        }

        public int Hour
        {
            get { return hour; }
            set { hour = value; }
        }


        public Microsoft.Office.Tools.CustomTaskPane MyCustomTaskPane
        {
            get { return myCustomTaskPane; }
            set { myCustomTaskPane = value; }
        }

        public void ThisAddIn_Startup(object sender, System.EventArgs e)
        {
            //MessageBox.Show("Start Up Called");
            myCustomTaskPane.VisibleChanged += new EventHandler(myCustomTaskPane_VisibleChanged);

        }
        public void setTime(int h, int m)
        {
            Hour = h;
            Min = m;
            myUserControl = new ctlClock(Hour, Min);
            //myUserControl = new ctlClock(0, 1);
            myCustomTaskPane = this.CustomTaskPanes.Add(myUserControl, "Remaining Time");
            myCustomTaskPane.Visible = true;
        }

        private void yCustomTaskPane_VisibleChanged(object sender, System.EventArgs e)
        {
            Globals.Ribbons.ManageTaskPaneRibbon.toggleButton1.Checked = myCustomTaskPane.Visible;
        }

        private void ThisAddIn_Shutdown(object sender, System.EventArgs e)
        {
        }

namespace MyWordAddin
{
    [ComVisible(true)]
    [InterfaceType(ComInterfaceType.InterfaceIsDual)]
    public interface IAddInUtilities
    {
        void setAddinTime(int h, int min);
    }

    [ComVisible(true)]
    //[Serializable()]
    [ClassInterface(ClassInterfaceType.None)]
    public class AddInUtilities : StandardOleMarshalObject,IAddInUtilities
    {
        public void setAddinTime(int hour, int min)
        {
            Globals.ThisAddIn.setTime(hour, min);          
            
        }

   }

    
}

namespace ControllerApplication
{
    public class CCWordApp
    {
        private Word._Application oWordApp;	// a reference to Word application

        public Word._Application OWordApp
        {
            get { return oWordApp; }
            set { oWordApp = value; }
        }
        private Word.Document oWordDoc;		// a reference to the document

        public Word.Document OWordDoc
        {
            get { return oWordDoc; }
            set { oWordDoc = value; }
        }

        public CCWordApp()
        {
            // activate the interface with the COM object of Microsoft Word
            oWordApp = new Word.Application();
            oWordDoc = new Word.Document();
            
            
        }

        // Open a new document
        public void Open()
        {
                object addinName = "MyWordAddIn";
                Microsoft.Office.Core.COMAddIn addin = oWordApp.COMAddIns.Item(addinName);
                IAddInUtilities utils = null;
                    utils = (IAddInUtilities)addin.Object;
                    utils.setAddinTime(0, 8);
          
            
            Object oMissing = System.Reflection.Missing.Value;
            oWordApp.Visible = true;
            oWordDoc = oWordApp.Documents.Add(ref oMissing, ref oMissing, ref oMissing, ref oMissing);
            oWordDoc.Activate();
        }