I’m not familiar with the technique that you’re using to create records when downloading data from Xero – can you explain how this works?
When downloading data from Xero if we need to create records in another table (e.g. Contacts, Invoices etc) rather than constantly changing layouts to create new records in the correct table we’re using a technique that allows you to create related records via a relationship that has the “Allow creation of records in this table via this relationship” enabled for the relationship.
This technique is also known as the “Magic Key” technique and is also used when implementing support for database transactions in FileMaker. You can read more about this technique at these websites: