I would like to commend you and your team for the great work you have done/ are doing with gibbon- development, maintenance and update. More importantly your decision to release this under GPL. I believe it requires alot of dedication and commitment.
I am now fully settled on the Admin module ->School Admin, System Admin, Timetable Admin and User Admin. The interface is good and the learning curve for the system is not steep.
Our timetable management policy requires a maximum occurrence of courses/subjects per week. For example you cannot exceed 5 occurrences of Mathematics per week. Is there a way we can enforce this validation in gibbon?