If you use the RM Recalc scripts for 'average days to pay', data exists for both customers in the ta780000 table, and so when you use the Customer combiner tool, it sees this as a duplicate record and you get this error:

Violation of PRIMARY KEY constraint 'PKta78000'. Cannot insert duplicate key in object 'dbo.tx78000'. The duplicate key value is (XXXXX).

Please make the customer combiner tool compatible with the 'average days to pay' RM scripts and not error on the ta78000 table. (CR #87802 - rejected)