Extending product function with VBA : System Architect collections : OfCollection class : SetProperty
  
SetProperty
Saves the property list within the OfCollection object. It is also important that the definition object itself is saved as this contains the property list to which the collection is saved.
Example
Dim i As Integer, oDef As Definition, coll As OfCollection
Set coll = oDef.GetPropertyAsCollection("Location Types")
coll.Add Chr(34) & "Regional Office" & Chr(34)
coll.SetProperty oDef.Save
See also
OfCollection class