Configure Accounting Subledger filter criteria to exclude specific GAU types or build a 3-object model without Opportunity

Steps:
To add GAU-based filter criteria:

1. Navigate to the Accounting Subledger app and open your Accounting Set.
2. In the Filter Criteria section, note that standard filter criteria is evaluated against the primary object (typically Opportunity). To filter based on GAU type, you must add criteria on the Allocation or GAU child objects within the Accounting Set object chain.
3. Add a filter condition on the General_Accounting_Unit__c object's Type or Category field (or the relevant picklist field that identifies the GAU type to exclude). Use the "Does Not Equal" or "Not Contains" operator to exclude the specific GAU types.
4. Save and test in a sandbox by creating Allocations with both included and excluded GAU types to verify Ledger Entry creation behavior.

To build a 3-object model (Payment → Allocation → GAU):

1. Create a new Accounting Set with Payment (npe01__OppPayment__c) as the primary object.
2. Add the Allocation (npsp__Allocation__c) object as the first child, related via the Payment lookup.
3. Add the GAU (npsp__General_Accounting_Unit__c) object as the second child, related via the Allocation lookup.
4. Configure Stage-to-State Mappings using "Uncommitted" and "Finalized" states as appropriate.
5. Set the Subledger Start Date to control which existing records are processed. For orgs with large data volumes (3M+ Opportunities), use the Start Date to limit initial processing scope and enable Accounting Review Mode to avoid processing all historical records on first run.
6. Test by creating a Payment with Allocations and confirm that Ledger Entries are generated at the Payment level without requiring an Opportunity record.