When we receive a batch payment from a vendor, which often includes invoices and credit memos, we have to apply the total amount with all the open invoices and credit memos. But we are not applying everything at the same moment because documents first have to be approved (especially by credit memos it can take a bit longer). So therefore open invoices and Credit Memos are appplied not at the same time. And when the amount of the batch payment goes to minus, because we still have some open credit memos that needs to be applied, the payment is closed and we can not use this anymore for applying the credit memos.

So please make it possible to apply credit memos against open payments.