Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
    System.EventArgs) Handles Button1.Click
    'Position des Panel auf dem Bildschirm
    Dim r As Rectangle = Me.Panel1.RectangleToScreen(Me.Panel1.DisplayRectangle)
    'Mittelpunkt des Panel
    Dim m As New Point(r.Left + r.Width / 2, r.Top + r.Height / 2)
    With Form2
      'Position der 2. Form
      .Location = New Point(m.X - .Width / 2, m.Y - .Height / 2)
      .ShowDialog()
    End With
  End Sub