We are in the process of using and testing the "Minimum required minutes in course" field under "Locking Options" to prevent users from printing certificate without spending the required time in the course.
We are trying to use this feature as an alternative to the "Time Spent (minutes)" field in the "Dependent on" section of Moodle Lessons.
During our tests, if we do not use the "Time Spent" field in the Lesson, the "Minimum required minutes in course" setting will not prevent a user from printing a certificate even though they have not spent the required time in the course.
The "Time Spent (minutes)" Lesson field is sufficient to impose a required amount of user time in the lesson, but Moodle documentation of Version 1.6 (and our testing of 1.9) verifies that the time spent is not cumulative. What we are trying to accomplish is to allow all of a user's time spent in the class count towards the required time to complete the course and obtain a certificate.
Can the certificate module act as the sole locking mechanism for timed, continuing education courses such as ours, and if so, can the "Minimum required minutes in course" be cumulative? Even if the certificate module cannot lock the certificate using cumulative time, is there a reason why users can proceed directly to the certificate during our tests, after only a few seconds (unless we use the non-cumulative "Time Spent (minutes)" field within the Moodle Lesson)?