Wait Dialog for Windows Forms

ShowWaitDialog.cs

private void ShowWaitDialog(Action codeToRun)
{            
    ManualResetEvent dialogLoadedFlag = new ManualResetEvent(false);
    
    // open the dialog on a new thread so that the dialog window gets
    // drawn. otherwise our long running code will run and the dialog
    // window never renders.
    (new Thread(() =>
    {
        Form waitDialog = new Form()
        {
            Name = "WaitForm",
            Text = "Please Wait...",
            ControlBox = false,
            FormBorderStyle = FormBorderStyle.FixedDialog,
            StartPosition = FormStartPosition.CenterParent,
            Width = 240,
            Height = 50,
            Enabled = true
        };

        ProgressBar ScrollingBar = new ProgressBar()
        {
            Style = ProgressBarStyle.Marquee,
            Parent = waitDialog,
            Dock = DockStyle.Fill,
            Enabled = true
        };

        waitDialog.Load += new EventHandler((x, y) =>
        {
            dialogLoadedFlag.Set();            
        });

        waitDialog.Shown += new EventHandler((x, y) =>
        {
            // note: if codeToRun function takes a while it will 
            // block this dialog thread and the loading indicator won't draw
            // so launch it too in a different thread
            (new Thread(() =>
            {
                codeToRun();

                // after that code completes, kill the wait dialog which will unblock 
                // the main thread
                this.Invoke((MethodInvoker)(() => waitDialog.Close()));
            })).Start();                                        
        });

        this.Invoke((MethodInvoker)(() => waitDialog.ShowDialog(this))); 
    })).Start();

    while (dialogLoadedFlag.WaitOne(100, true) == false)
        Application.DoEvents(); // note: this will block the main thread once the wait dialog shows
}

Is there an easy way to add an elapsed timer to this?