Solution : https://service.sap.com/sap/support/notes/654876 (SAP Service marketplace login required)
Key words : 
select function module -> display <-> change, attached source code corrections, select function module mrtrs965_bom_generation, enter function group mrtrs965, start transaction se80, et_message               type spec, terms recipe management, generated alternative boms, source code, function module
Related Notes : 
       
| 631420 | RMGMT210: Corrections in Support Package 04 |