Solution : https://service.sap.com/sap/support/notes/1074313 (SAP Service marketplace login required)
Key words : 
system displays distribution rules, generated settlement rule, display mode, master data, internal order, transaction ko03, transaction ko02, strategy sequence, ksr3_orc reason, program error
Related Notes : 
       
| 1079277 | Settlmnt rule: Adjusting generated rules in coll. processing | 
| 969602 | Current Release Restrictions for DBM 6.0 | 
| 967485 | Internal order: Automatic generation with BAPI | 
| 961227 | Settlement rule from BAPI_INTERNALORDER_CREATE incorrect | 
| 604127 | Int.order without settl.rule if creating from Appr. Request | 
| 503993 | Claim: Settlement rule not taken from strategy sequence |