Just pull it off gently, no tools required. Years ago, I owned the original CDM1, same grille.
Use this link and navigate to the CDM1 SE, you will see a drawing that should help you understand.
http://bwgroupsupport.com/manuals/service
Use this link and navigate to the CDM1 SE, you will see a drawing that should help you understand.
http://bwgroupsupport.com/manuals/service