I thought the inside mecanism was:
SELECT *
FROM ORDERS
WHERE CUSTNO=:P_CUSTNO
And put on MasterParamLinks:
P_CUSTNO=CUSTOMER.CUSTNO

IBO Retrieves master CUSTOMER.CUSTNO and place it into a variable
labeled as "P_CUSTNO"

Use that label to associate
ParamByName('P_CUSTNO').Value = P_CUSTNO.VALUE

so P_CUSTNO can be "P_WHATEVER", since is chained to the field in the
WHERE by the WHERE itself (WHERE CUSTNO=:P_WHATEVER).
If not, I don't see really advantages over MasterLinks where field
names must be the real ones... or there are situation where you can't
do without MasterParamLinks?
Regards
Marco Menardi