So you are suggesting to use the temporary crontab file instead of just using a blank one and save it under /etc/crontab?
I'm familiar with crontab files and I love their flexibility and options. It's more than the GUI provides
Kind of became a command line guy now...
It only leaves the question of where the existing (and functioning) cron job from the GUI went.
If I make another crontab file, I may end up running a job twice (or not at all if there's a clash). So could go and delete the one from the GUI.