Solution : https://service.sap.com/sap/support/notes/640158 (SAP Service marketplace login required)
Key words : 
primavera p3 reason, complex collective orders, collective orders, bapis bapi_alm_order_maintain, terms bus2007a, modules bapi_alm_order_maintain, solution implement, bapi_alm_order_get_detail takes, bapi_alm_order_get_detail, processing
Related Notes : 
       
| 736204 | Notes for downgrade kit ALMBAPI I | 
| 708508 | Downgrade BAPI_ALM_ORDER_MAINTAIN -> errors | 
| 642831 | Error message IW 161 when creating order |