Solution : https://service.sap.com/sap/support/notes/631062 (SAP Service marketplace login required)
Key words : 
sales order-specific configuration, individual requirements inventory, sales order, configuration assigned, configured material, material variant, master data, cost estimate, components derived, material master
Related Notes : 
       
| 683033 | CK11N and multi-level configuration | 
| 672566 | CK11N: Incorrect display for multi-level configuration | 
| 361668 | Production order: configurable material variants |