Solution : https://service.sap.com/sap/support/notes/558157 (SAP Service marketplace login required)
Key words : 
previously selected report, selection works correctly, bw support packages, 0bimport support package 6, web reporting reason, 0b support package 6, support package, web reporting, web report, correctly finds
Related Notes : 
       
| 558117 | Long OLAP runtime for special queries (COLLECT_S FORM) |