Solution : https://service.sap.com/sap/support/notes/1251389 (SAP Service marketplace login required)
Key words : 
edit report templateyou, edit report template, 7b support package 18, attached correction instructions, support packages, symptom component, product safetymodule, badi ehss_wwi_badi_001, enhancing functions, transaction cg42
Related Notes : 
       
| 1512213 | EH&S WWI: Error when editing symbols | 
| 1272246 | Problems during syntax check for report templates | 
| 1160624 | EH&S WWI: Error 5825 when editing report from template | 
| 964078 | EH&S WWI: Error in BAdI for editing report template | 
| 568302 | Current version of EH&S WWI and EH&S Expert |