Allen Browne's Audit Log code

There is a lot of stuff here.  Please bear with me.  I'm trying to implement Allen Browne's Audit Log

http://allenbrowne.com/AppAudit.html   The pdf is attached.

I've studied it and added the code as described to my app.

I want to understand the how it is supposed to work(of course I have errors too)

There are four functions.  Right now I'm focused on edit.

The AuditEditBegin("Diodes", "audTempDiodes", "audID", Nz(Me.audID, 0), bWasNewRecord) function is called in the form BeforeUpdate event.  

The AuditEditEnd("Diodes", "audTempDiodes", "audDiodes", "audID", Nz(Me!audID, 0), bWasNewRecord) function is called in the form AfterUpdate event.  

So if I open the form to edit a record.  Then edit a text box value.  When is the form BeforeUpdate event called?  

When is the form AfterUpdate event called?

...and

... the Nz(Me.audID,0)  in AuditEditBegin It is supposed to be passing the value of the field audID.  But when executed I get Compile error: Method or data member not found and .audID is highlighted.

Here is the function call and function:
Call AuditEditBegin("Diodes", "audTempDiodes", "audID", Nz(Me.audID, 0), bWasNewRecord)

Function AuditEditBegin(sTable As String, sAudTmpTable As String, sKeyField As String, _
    lngKeyValue As Long, bWasNewRecord As Boolean) As Boolean
'On Error GoTo Err_AuditEditBegin
    'Purpose:    Write a copy of the old values to temp table.
    '            It is then copied to the true audit table in AuditEditEnd.
    'Arugments:  sTable = name of table being audited.
    '            sAudTmpTable = name of the temp audit table.
    '            sKeyField = name of the AutoNumber field.
    '            lngKeyValue = Value of the AutoNumber field.
    '            bWasNewRecord = True if this was a new insert.
    'Return:     True if successful
    'Usage:      Called in form's BeforeUpdate event. Example:
    '                bWasNewRecord = Me.NewRecord
    '                Call AuditEditBegin("tblInvoice", "audTmpInvoice", "InvoiceID", Me.InvoiceID, bWasNewRecord)
    Dim db As DAO.Database           ' Current database
    Dim sSQL As String

    'Remove any cancelled update still in the tmp table.
    Set db = DBEngine(0)(0)
    sSQL = "DELETE FROM " & sAudTmpTable & ";"
    db.Execute sSQL

    ' If this was not a new record, save the old values.
    If Not bWasNewRecord Then
        sSQL = "INSERT INTO " & sAudTmpTable & " ( audType, audDate, audUser ) " & _
            "SELECT 'EditFrom' AS Expr1, Now() AS Expr2, NetworkUserName() AS Expr3, " & sTable & ".* " & _
            "FROM " & sTable & " WHERE (" & sTable & "." & sKeyField & " = " & lngKeyValue & ");"
        db.Execute sSQL, dbFailOnError
    End If
    AuditEditBegin = True

Exit_AuditEditBegin:
    Set db = Nothing
    Exit Function

Err_AuditEditBegin:
    Call LogError(Err.Number, Err.Description)
    Resume Exit_AuditEditBegin
End Function


Thanks,
Brooks