How to ignore Grand Total Rules?

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Well, credit notes are in the JV module, is nothing that we can send to the customer that is listing the products, amount and grand total, like a bill, actually what is needed is a bill just that allows negative values, should not be so difficult to bypass this restriction.

I think this issue remains since 1year+ and is properly documented in the community, it would be great to have a solution. Another thread about it here:

Generating Credit Notes

How can I generate a credit note for customer? I know we can do a journal entry in the JV module. But here we need to generate the credit note document and send it to customer. For example, we have a sales campaign and we will send credit note to the customers if they hit certain figures and they can use the credit note to offset future purchase.