Well as it was told in that thread you had there going you would have to check if you have the file tv_grab_zap2epg in /usr/bin and what permission owner it has.
Open command line (see below) and run ls -lah /usr/bin/tv_grab_zap2epg and show us the output.
Details regarding how to access the command line interface can be found here on our Wiki: Accessing the command line - General - OSMC