Solution : https://service.sap.com/sap/support/notes/581957 (SAP Service marketplace login required)
Key words : 
material detail screen, rounding solution implement, material overview, implement note 585187, production order, process order, base quantity, terms co01, source code, 3 decimal places
Related Notes : 
       
| 658086 | Rounding requirements qty of components during order creatn | 
| 649997 | |
| 620532 | |
| 585187 | |
| 542554 | |
| 444944 |