Run the "Create Advanced Accounting Override" procedure from the action menu of the Program registration config record.
Afterwards, navigate to the GL Defaults query located on the System Homepage in your Accounting database. The name of the GL Defaults should begin with the access name of the Program registration config record.
There should be two GL Defaults, one for Cash and one for Credit. Program Registration Simple Receipts will come in as "Misc Cash Receipts" and will Debit the Cash Account and Credit that Revenue Account.