Solution : https://service.sap.com/sap/support/notes/211656 (SAP Service marketplace login required)
Key words :
initial screen choose object component, additional key words 1b001, bkk42-acnum_ext reference type, field blank proposal, field blank optional, message class 1b, change function module, field/structure, function module, function modules
Related Notes :
| 196060 | SAP Banking 4.03A Add-On Patch SAPKIPBE05 / BF05 |