Shell HSSE Specialist interview questions

I applied for the graduate program with Shell. The first round was the telephone interview after I passed the CV screening. Questions were structured according to Shell CAR criteria. This round is quite easy if you know yourself well and prepared for some standard interview questions. I succeeded with this round and was then invited to the SRD(Shell Recruitment Day) in Holland. It consisted of three modules: case study, group work, technical presentation. I feel the case study is most tricky. I had a lot materials to read and need to find key issues and propose strategic solutions within 1h20mins. The technical presentation was also not easy. I was given the opportunity to present some of the research stuffs related to the position I applied for. However, it seems I didn't make it easy-understood to my audience(1 technical manager+ 2 non-technical assessors).