arcobjects - How to make sure OnSketchFinished always works?

In my VBA application I have a listener set up that listens for OnSketchFinished, when the polygon is created a message box appears and then a userform.

My problem is that the listener will work 90% of the time, not 100%.

Here are the snippets of code in ThisDocument:

Private WithEvents EditEvents As Editor
Private m_pEditor As IEditor
Public Sub SetEvents()    

    ' This is the listener for the Editor
    Dim pID As New UID
    pID = "esriEditor.Editor"
    Set m_pEditor = Application.FindExtensionByCLSID(pID)
    Set EditEvents = m_pEditor
End Sub

Private Function MxDocument_OpenDocument() As Boolean
    Call SetEvents
End Function


Private Sub EditEvents_OnSketchFinished()
    Call frmCityDev.EditEvents               
End Sub

In my form I have code for EditEvents which brings up a msgbox to notify that a new polygon has been created.

Am I missing something to make sure that the listener will always work?