Testcase to check Partner Relations are created correctly without exceptions.
Open window BPartner, search for G000X
Press Process, create partner relation
Select an address for G000X, then set G000Y as related partner and select an address for G000Y
Check isBillto, then OK
Open window Partner Relation, search for G000X
Go back to windo BPartner, G000X
Press Process, create partner relation
Select an address for G000X, then set G000Z as related partner and select an address for G000Z
Check sth else, e.g. Delivery Standard, OK
Open window Partner Relation, search for G000X