Hi Rick

One suggestion is to have multiple seminar activities in the same course and to restrict access to events based on the completion of other activities. The restrict access is not available for individual events unfortunately. You should use the show activity setting so learners can still see the seminar activity but they won't be able to access this.

Approval of the signup to events can also be limited to specific trainers using event roles. Once the learner has met the requirements then the learner would signup for the event and the relevant event trainer would approve the learner.

regards