Many Thanks Veselina for your prompt reply!
I am currently trying to design a solution and i am considering creating a new pre-payment copied from SAP standard debit memo, there will of course be an order related invoice going out to the customer for payment, Like i explained earlier, when the invoice is cleared, delivery block removed, a standard delivery document has to be created, for example based on SAP standard 'LF' but in the case of the delivery related invoice, it will be a proforma as the original invoice has already been paid
Do you Think this solution will work? have you got any further tips how you configured this solution for your clients?
Thanks