hi WED to be honest with you I got information from that CIC site so please take advise from Agent before you make an application.
I too saw the CIC site and it says about C41 to C45 categories but doesn't specify that we need to put C41 in "intend to work" column.
Further, as per IMM 5488, it clearly mentions that if Open Work Permit, leave 2 to 6 fields blank.