Private Declare Function GetAsyncKeyState Lib "user32" (ByVal vKey As Long) As _
  Integer
 
Private MOUSE_LINKS As Boolean
Private Const VK_LBUTTON = &H1
Private Resize_Angefordert As Boolean
 
Private Sub Form_Load
    Me.Timer3.Intervall = 150: Me.Timer3.Enabled = True
    ...
End Sub
 
Private Sub Form_Resize()
    Me.Timer4.Enabled = True: Resize_Angefordert = True
End Sub
 
Private Sub Timer3_Timer()
    If GetAsyncKeyState(VK_LBUTTON) Then MOUSE_LINKS = True Else MOUSE_LINKS = _
      False
End Sub
 
Private Sub Timer4_Timer()
    If Resize_Angefordert = True And MOUSE_LINKS = False Then Call RESIZE_JETZT
End Sub
 
Private Sub RESIZE_JETZT()
 
   '...Resize-Vorgang ausführen
   '...Resize-Vorgang ist erledigt
 
    Resize_Angefordert = False: Me.Timer4.Enabled = False
End Sub