Solution : https://service.sap.com/sap/support/notes/89557 (SAP Service marketplace login required)
Key words : 
additional key words ck11, attached source code corrections, quantity structure determination, quantity structure, cost estimate, component quantities, costing variant, transaction okk5, error occurred, indicator '1'
Related Notes : 
       
| 115011 | CK11: Usage probability for alternatives | 
| 100901 | COR1,COR2: Chnge header qantity=>cmpnent quantities | 
| 73033 | Component quantity in production orders |