Develop a Commercial Invoice on AX 2012

Hi,
Currently,IamworkinginAX2012;Ineedtodevelopa"commercialinvoice"reportsimilartoPerforma packingslipreportontheSalesorderform.Ineedaseparateactionbuttoncommercialinvoiceonnexttothe"Performapackingslip" button. 

Itisonlyusedforcustoms'valuation.Onceclickeditwillgenerate the commercialinvoicereportforarecentitems "packingslip"ed.

I can develop a new report, how to integrate with this to the "SalesEditLines" formsOK button.Ijustneedtounderstandhowtodothisandwheretostart. 

Thankyouinadvance...