Solution : https://service.sap.com/sap/support/notes/76177 (SAP Service marketplace login required)
Key words : 
menu item environment -> acct grp assignmentplace, party                                xpy - payer                                        xsh - ship-, transaction vopaselect sales document headerclick, germany            sapserv4 - foster city, maintain partner procedures customer master, monthly arrears billingbilling rule, monthly advance billingbilling rule, quarterly advance billingbilling rule, installation solution catt documentation, /specific/issw/catt file
Related Notes : 
       
| 73031 | Additional Customizing Req'd for IS-SW 1.2A | 
| 63841 | Release Information of R/3 Add-On IS-SW & IS-HT |