AAWS: Initiate ePayment Fails with Custom Application Child Entity - Resolved(?)

For AAWS developers' information and education (and possibly, entertainment).

We (MacEwan University) are currently building a front-end application to take applications for admission using PeopleSoft AAWS. We decided to add one custom staged child entity to the delivered Application entity, in order to store some local specific data in an existing custom record/table. Since the existing record already mimicked the key structure of the Career Sequence record (that is, a proper child-of-application key structure), the process was pretty straightforward:

• Copy the existing record to a staging version.
• Remove EMPLID, add SCC_TEMP_ID.
• Build the database table.
• Create empty entity class in an App Package.