Hi Ian. What about something like this:
// create the specific enum you are looking for
CustomersFieldIndex fieldEnum = (CustomersFieldIndex) Enum.Parse(typeof(CustomersFieldIndex), "CustomerId");
// possible uses: create a field to use in a filter
EntityField2 field = (EntityField2) EntityFieldFactory.Create(fieldEnum);
// use in a filter
IRelationPredicateBucket filter = new RelationPredicateBucket();
filter.PredicateExpression.Add(field == "ALFKI");
