Screenshots and keylogs have two separate timers. Eventually you may want to receive screenshots every 30 minutes but keylogs once every 6 hours. You're free to setup your custom wanted time intervals.
Atom logger can send you instant notifications via email if certain "blacklisted" keywords are typed. You can define these keywords when creating your build.
Today I will delete all builds backups copies from my server to save disk space. Tens/hundreds of builds are created each week and this is a task performed on weekly basis.
Pay attention to SSL and not-SSL SMTP settings when configuring your delivery options, if you want to receive keylogs via email. Sometimes using SSL may prevent you from receiving your logs.
This is a security tool that has been designed to monitor computers you own. Using Atom Logger or similar applications to spy other people is illegal and it hasn't been developed for this purpose.