Hello,
In O7FB you can define the fields that can be used to sort the payment proposal payment.
You can define a default layout to be used in the Display/Edit Payment Proposal, and then in F110 specify the sort sequence once thelist is displayed.
FAKP > Periodic Processing > Payment autom.pmnts > Line Layout
FAKP > Periodic Processing > Payment autom.pmnts > Default values >
and for transaction FBZ0 select the defined Layout
From release 5.0 the payment proposal processing was changed to the ALV. With this tool the line structure is determined - as in all ALV lists -within the application. During the use of the ALV the "old" Customizing settings are obsolete. Hence in your case with ALV option, the Proposal -> edit -> Settings -> Line Layout is greyed out. The note number 617492 is useful to understand this new funcionality.
As an alternative also I would suggest you to use proposal list , program RFZALI20.
I hope this helps.
Oscar