Solution : https://service.sap.com/sap/support/notes/555143 (SAP Service marketplace login required)
Key words :
class cl_rsr_grid method prepare_formats, advance source code corrections, solution import support package 06, termination getwa_not_assigned occurs, hierarchy opening operations, bw support packages, 0b support package 06, support package, 0b-patch06, sapbwnews bw 3