Solution : https://service.sap.com/sap/support/notes/320068 (SAP Service marketplace login required)
Key words :
sgrw_docu_cons_notesgrw_om sgrw_ps sgrw_pc sgrw_sl sgrw_pca sgrw_ec sgrw_lis, symptom unexpected warning gr519 - 'threshold, additional key words gr519 threshold, settings->layout->page control, flag 'change allowed, report->save settings, edit-> threshold, report settings, report layout, report output
Related Notes :
| 353704 | Composite note 'Threshold value' |
| 173172 | Rp.for setting 'Change w/output' for Rep.Writer reports |