Solution : https://service.sap.com/sap/support/notes/777683 (SAP Service marketplace login required)
Key words :
system issues message sv 066, quantity-based overhead rates, edit > selections > select block, overhead rate change, lines remain deselected, select block end, select block, line block, detail view, costing sheet
Related Notes :
| 126551 | Composite note: Customizing of costing sheet |