What is the recommended approach for dealing with complex messages governed by external standards (Edifact, ASC X12, cXML, etc.)? Such messages are often very complex, and they are not related to our notion of entities. Should one translate their schemas into CDS representations? Difficult to imagine, at least if one wants to leverage entities, rather than describe the entire tree structure with nested "type"s. And how to accomplish the complex transformations required to translate between such external messages and CAP service messages as well as other external messages?