Hi Sonia
An action needs to occur to trigger the Reminder emails. For this we normally use Course Completion and less often the marked attendance in a F2F session (when the course assessment is weeks or months after the training in person).
To get around sessions where attendance isn't taken we have a local customisation, which we're happy to share, in the F2F instance that "Automatically mark fully attended" immediately after the session. This then triggers the course evaluation.
Our whole Level 1 process was covered in our iMoot 2011 presentation attached.
Hope this helps
Austen