I tried to set up mail notifications when file, folder has been changed, but I didn’t get any emails for files or folders that I created BEFORE I set it up.
But, after that, when I created folders or files changes are reported. So hope this helps because I was going crazy why things don’t work, couldn’t find explanation online and I eventually created simple bash script and cronjob to notify me. Of course, it was a simple solution and offical app is much better and gives more information of activity.