How do I copy or delete tasks (or activities) quickly and easily?

Once you have set up a task (or activity) exactly as you want it -- with min and max helpers as required --  you can use the copy button on the task page and edit the copied task right away like this (video 49 secs):

Alternatively you can copy and edit tasks directly from the task list as shown in this 23 second video here (same goes for activities):