Funzionamento del registro
Register activity organizes logs of courses in sessions: each session has login and logout. If register is in a normal course, it will calculate only logs from that course, if it's in a metacourse, it'll calculate all logs of courses in that category. Login is the first log for the course (or of categories) if there aren't any other logs before the timeout period, Register activity creates a logout. For this activity you can also set a probability evaluation for logout and you can give to the users the possibility to certificate the time they spent offline to study.