The integration pulls sales information (invoices, credit notes, receive money transactions, and payments) and transforms the data into a way that it can be connected and sent to ChartMogul.
When pulling the data from Xero it will try to automatically transform the data into the required format for sending it on to ChartMogul. For data that has the appropriate information, this is an automatic process. For data that does not have the necessary information, the transactions are sent to a review queue in SaaSync where you can manually update the missing fields on the record before sending it on to ChartMogul.
This video below is a good demonstration of what the integration does.