Sorry to be dense Kevin.  But Im having a difficult time understanding the nuance of AfterUpdateDlookup.  I know your previous solution worked but I have three more instances on this form that I hope to get to work; Suburb/PostalCode, PresentOffice/OfficeRanking and MemberType/Annual Dues.   Right now, Im working on PresentOffice/OfficeRanking and it does not work.  
OfficeRanking is a Numeric Field that I use to sort and group members in different reports.  The OfficeRanking values are changed each year when members hold different offices.

Suburb/PostalCode are both Short text fields.  I hope it will be the same structure as the last one you helped with.
MemberType/Annual Dues  MemberType is short Text and Annual Dues is currency.  

This is what I think AfterUpdate Dllokup for PresentOffice/ OfficeRanking should be but it does not work.

Private PresentOfficeCbo_AfterUpdate()
Form's NameTargetField = Nz(Dlookup(HelperTable"FieldName", "HelperTableName", Form's "FieldName=""" & Form's ComboFieldName.Column(1) & """), "")

End Sub

Private PresentOfficeCbo_AfterUpdate()
    OfficeRanking=Nz(Dlookup("OfficeRanking","Mem_125_LodgeOffice_HT","PresentOffice="""&PresentOfficeCbo.column(1)&"""),"")

End Sub