Editing the crontab

We have a shared directory (/home/shared) on our computer and a usergroup called "shared". The purpose is that we put things there that should be accessible (including writable) to several users of the system. If one user puts a file there, it can be read by others but not e.g. deleted. In order to fix this, we edited the crontab to execute every 5 minutes the following two commands:

chgrp -R shared /home/shared
chmod -R 744 /home/shared

In order to do this we edited (as root of course) the /etc/crontab file by adding the line:

*/5 * * * * root run-parts /etc/cron.minutely

This means execution every 5 minutes, every hour, every day, every month, every weekday the script run-parts should be executed as root taking all scripts from the /etc/cron.minutely as argument (we created this directory newly in addition to the already existing /etc/cron.hourly, etc.). We restarted crond (the crontab deamon) via the GUI (under RedHat 9 Menu-System Settings-Server Settings-Services).