Solution : https://service.sap.com/sap/support/notes/1330078 (SAP Service marketplace login required)
Key words :
select web dynpro component / interface, details button remains disabled, account assignment overview screen, account assignment details screen, menu option create --> attribute, node comp_context --> accounting --> m_dv_accounting, node comp_context --> accounting --> m_de_accounting, accounting overview screen, software component srm_server, account assignment data
Related Notes :
1563848 | Accounting fields non-editable for '*' product category |
1457285 | FAQ: Accounting PO Transfer, FI/MM Validation Errors |