Form lost focus

Question

With the help of this link i made a splash screen. It works but the form which starts after the spash screen doesn't get the focus anymore. I need to activate it with a mouse click

Program.cs

static void Main()
{
    Application.EnableVisualStyles();
    Application.SetCompatibleTextRenderingDefault(false);

    //show splash
    Thread splashThread = new Thread(new ThreadStart(
        delegate
        {
            splashForm = new FormSplashScreen();
            Application.Run(splashForm);
        }
        ));

    splashThread.SetApartmentState(ApartmentState.STA);
    splashThread.Start();

    //run form - time taking operation
    FormQueryBoxMain mainForm = new FormQueryBoxMain();
    mainForm.Load += new EventHandler(mainForm_Load);
    Application.Run(mainForm);

    // Application.Run(new FormQueryBoxMain());
}

static void mainForm_Load(object sender, EventArgs e)
{
    //close splash
    if (splashForm == null)
    {
        return;
    }

    splashForm.Invoke(new Action(splashForm.Close));
    splashForm.Dispose();
    splashForm = null;
}

Main Form

private void FormMain_Load(object sender, EventArgs e)
{
    Logging.StartLogging();  //this just starts the logging  
}   

private void FormMain_VisibleChanged(object sender, EventArgs e)
{
    if (CheckLicense())
    {
        LoadTreeViewQueries();

        //Inlog
        FormGebruikerInlog ApplicatieLogIn = new FormGebruikerInlog(this, "Inlog Gebruiker");

        ApplicatieLogIn.ShowDialog(this);  --> This lost the focus.
    }
    else
    {
        LoadLicenseForm(); //Inlog voor licentie direct starten
    }
}   

ApplicatieLogIn.ShowDialog(this); the form doesn't have the focus anymore.

First i had the code from FormMain_VisibleChanged in the FormMain_Load standing and then ApplicatieLogIn opened on top and had focus But that is not possible any more now i add the spashscreen. How can i give ApplicatieLogIn the focus back?

this.focus(); or this.actitive() in the load of the ApplicatieLogIn doesn't the trick.