If you set up a repeat item with a reminder, the reminders stop coming if you miss marking one of them as completed. This behavior is not correct. Just because you missed checking off a daily item yesterday doesn't mean you don't want to be reminded again today. A repeat reminder should go off no matter what happened the times before.
Reminders can only be sent for tasks that exist somewhere. The way repeating tasks work is that the next one is not generated (does not exist) until the previous one has been completed. One thing you might try is looking into the "optional" Due Date modifier. If a repeating task is optionally due, it will disappear once it's Due Date has passed, and the next occurrence will be generated. So if I have a daily repeating task due today with a reminder, and don't complete it, another one will appear due tomorrow with the reminder set.