Ayuda con este Keygen VB 2008

Saludos!

Tengo el siguiente Keygen que genera varias claves..

Ire por fila y nombramientos

Text Box 1: Donde la persona pondra su Nombre.

Text box 2: Donde saldra el Key

Check Box 1: Donde marcara si es la version vieja [Key 16 digitos]

Check box 2: Donde marcara si es la version moderna [Key 20 digitos]

Botton 1: El boton de generar

Este es mi codigo:

Código

Public Class Form1
 
    Private Sub Label1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
 
    End Sub
 
    Private Sub CheckedListBox44_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
 
    End Sub
 
    Private Sub iCT_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
 
    End Sub
 
    Private Sub INGENUITY_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
 
    End Sub
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
 
    End Sub
 
    Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
 
    End Sub
 
    Private Sub CheckBox6_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox6.CheckedChanged
 
    End Sub
 
    Private Sub CheckBox5_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox5.CheckedChanged
 
    End Sub
 
    Private Sub CheckBox4_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox4.CheckedChanged
 
    End Sub
 
    Private Sub CheckBox9_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox9.CheckedChanged
 
    End Sub
 
    Private Sub CheckBox8_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox8.CheckedChanged
 
    End Sub
 
    Private Sub CheckBox7_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox7.CheckedChanged
 
    End Sub
 
    Private Sub TextBox2_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox2.TextChanged
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        TextBox2.Text = Int(Rnd() * 5)
        Select Case TextBox2.Text
            Case 0
                TextBox2.Text = "71587E67012990840EC0913F7EB17FDCEC2A43BF3523014C0432BF44075435FC"
            Case 1
                TextBox2.Text = "CC227E5F012990BE4E476CC2834C8223C1C7BE42C8DEFCFA21DC52A9FB69C7BD"
            Case 2
                TextBox2.Text = "43C67E5D012990BEAAC807A9E827E94A7ABCD529A3B597DA92A429D291C2A36A"
            Case 3
                TextBox2.Text = "5DA27BED012990BEC6D6759B9A5D9EC808CEA75BD1C7E5A8E0DE5BA0E3B0D118"
            Case 4
                TextBox2.Text = "7AF7BF290122547A93FA07E9E82FECBA7ABCD529A3B597DA92AC29D291C2A36A"
        End Select
    End Sub
 
    Private Sub CheckBox1_CheckedChanged_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged
        Handles CheckBox1.CheckedChanged 
        If CheckBox1.Checked Then
            TextBox1.Enabled = True
        Else
            TextBox1.Enabled = False
        End If
    End Sub
 
    Private Sub CheckBox2_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox2.CheckedChanged
        Handles CheckBox2.CheckedChanged 
        If CheckBox2.Checked Then
            TextBox1.Enabled = True
        Else
            TextBox1.Enabled = False
        End If
    End Sub
End Class

Mis problemas...

1- No se como hacer que sea obligatorio escribir algo en mi Text box 1 para asi te permita presionar el Botton 1.

2- Cuando trato de compilar este codigo:

Código:


    Private Sub CheckBox2_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox2.CheckedChanged
        Handles CheckBox2.CheckedChanged 
        If CheckBox2.Checked Then
            TextBox1.Enabled = True
        Else
            TextBox1.Enabled = False
        End If
    End Sub

Es para que el Text box este oculto y sea obligatorio seleccionar uno de los CheckBox para habilitarlo. Al ejectuarlo me da error de Sintax en el area de: "Handles"; Me lo podrian explicar?

3- Se como hacer que salga un Key en un rand.. pero no se como hacer para que cuando yo seleccione el CheckBox 1 solo se active el rand de las Key de 16 y si selecciono el CheckBox 2 solo se active el rand de las key de 20.

Saludos!

Private Sub Form1_Shown(sender As Object, e As EventArgs) _
Handles MyBase.Shown
button1.enabled = false
End Sub
Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) _
Handles TextBox1.TextChanged
button1.enabled = String.IsNullOrEmpty(CStr(sender.text))
End Sub

private KeyLength as integer = -1I
Private Sub Form1_Shown(sender As Object, e As EventArgs) _
Handles MyBase.Shown
CheckBox1.tag = 16I
CheckBox2.tag = 20I
End Sub
Private Sub CheckBox_CheckedChanged(ByVal sender As Object, ByVal e As EventArgs) _
Handles CheckBox1.CheckedChanged, CheckBox2.CheckedChanged
KeyLength = CInt(sender.tag)
End Sub
private sub GenerarRandomKey()
Select case KeyLength
Case Is 16I
Case Is 20I
End Select
End sub