Course-setting can be a large time commitment depending on the event duration (e.g. 6 or 24hr) and location but a very rewarding experience. A number of weekends may be required to locate a suitable area, set and vet the course. Forward planning is required so that permission for land use is gained in good time prior to the event. The longer you have to plan an event before it takes place, the easier the task.
Admin helpers, general helpers and first aid are on the day only jobs, which require very little forward planning.
Admin Manager requires an ongoing time commitment prior to the event to monitor entries as well on the day. ACTRA's online entry system is highly automated, so it's mainly team changes and answering queries that takes time.
Setting and vetting can take from a couple of days to several full days depending on the complexity of the course, your navigation ability and fitness levels and distance you need to travel to the course.
If you are interested in setting and coordinating an event this is a considerable time commitment.