Code locking up until I press the reset button

I have the following code:

'the following code is for the first userform that displays on _open

Option Explicit

Const GWL_STYLE = -16
Const WS_CAPTION = &HC00000
Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" _
(ByVal hWnd As Long, ByVal nIndex As Long) As Long
Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" _
(ByVal hWnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As
Long
Private Declare Function DrawMenuBar Lib "user32" (ByVal hWnd As Long) As Long
Private Declare Function FindWindowA Lib "user32" (ByVal lpClassName As
String, _
ByVal lpWindowName As String) As Long

Private Sub Userform_Initialize()

Dim lngWindow As Long, lFrmHdl As Long

lFrmHdl = FindWindowA(vbNullString, Me.Caption)
lngWindow = GetWindowLong(lFrmHdl, GWL_STYLE)
lngWindow = lngWindow And (Not WS_CAPTION)

Call SetWindowLong(lFrmHdl, GWL_STYLE, lngWindow)
Call DrawMenuBar(lFrmHdl)

End Sub

'The code above does nothing more than display the userform without a title
bar

Private Sub AddButton_KeyDown(ByVal KeyCode As MSForms.ReturnInteger, _
ByVal Shift As Integer)

Dim A As Integer

If Chr(KeyCode) = "A" Then
AddTitle.Show
End If

End Sub

'the following code is for the next userform that displays when you hit the
A key

Option Explicit

Const GWL_STYLE = -16
Const WS_CAPTION = &HC00000
Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" _
(ByVal hWnd As Long, ByVal nIndex As Long) As Long
Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" _
(ByVal hWnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As
Long
Private Declare Function DrawMenuBar Lib "user32" (ByVal hWnd As Long) As Long
Private Declare Function FindWindowA Lib "user32" (ByVal lpClassName As
String, _
ByVal lpWindowName As String) As Long

Private Sub Userform_Initialize()

Dim lngWindow As Long, lFrmHdl As Long

lFrmHdl = FindWindowA(vbNullString, Me.Caption)
lngWindow = GetWindowLong(lFrmHdl, GWL_STYLE)
lngWindow = lngWindow And (Not WS_CAPTION)

Call SetWindowLong(lFrmHdl, GWL_STYLE, lngWindow)
Call DrawMenuBar(lFrmHdl)

End Sub

When I step through this code it works BUT once the AddTitle userform (the
last userform) displays I can't Alt-F11 to get back to VBE. I can manually
get there with the mouse but once there I have to hit the reset button to
access my code again. Why am I hanging up?