// тут всякие атрибуты для COM Expose
    public class MyBeautifulControl : UserControl, IMyBeautifulControl 
    {
        [ComRegisterFunction()]
        public static void RegisterClass(string key)
        {
            using (RegistryKey k = Registry.ClassesRoot.OpenSubKey(TrimClassesRoot(key), true))
            {
                RegistryKey ctrl = k.CreateSubKey("Control");
                ctrl.Close();
            }
        }

        [ComUnregisterFunction()]
        public static void UnregisterClass(string key)
        {
            using (RegistryKey k = Registry.ClassesRoot.OpenSubKey(TrimClassesRoot(key), true))
                k.DeleteSubKey("Control", false);
        }
    }

//экспортируемый контрол
public class MyControl : UserControl, IMyControl
{
        #region Arrow Keys Management

        private const int WM_GETDLGCODE = 0x0087;
        private const int WM_KEYDOWN = 0x0100;
        private const int WM_KEYUP = 0x0101;

        private const int DLGC_WANTARROWS = 0x0001;

        [DllImport("User32.dll")]
        private static extern int SendMessage(IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);

        protected override void WndProc(ref Message m)
        {
            if (m.Msg == WM_GETDLGCODE)
            {
                m.Result = (IntPtr)DLGC_WANTARROWS;
                return;
            }

            if (m.Msg == WM_KEYDOWN || m.Msg == WM_KEYUP)
            {
                int keyCode = (int)m.WParam;
                if (keyCode == (int)Keys.Left || keyCode == (int)Keys.Right ||
                    keyCode == (int)Keys.Up || keyCode == (int)Keys.Down)
                {
                    Control activeControl = FormUtils.GetActiveControl(this);
                    SendMessage(activeControl.Handle, m.Msg, m.WParam, m.LParam);
                    return;
                }
            }

            base.WndProc(ref m);
        }

        #endregion
}

public static class FormUtils
{
        public static Control GetActiveControl(Control ac)
        {
            while (ac != null && ac is IContainerControl)
                ac = ((IContainerControl)ac).ActiveControl;
            return ac;
        }
}

var ctl = new UserControl1();
ctl.Parent = Control.FromHandle(ParentWindowHandle);