The use of MTBO mapping standards is a clever move IMO. They focus on the trail network, and the course planner can fix up details off-trail to support interesting control sites.
Years ago, we became frustrated with the standard topo mapping and started putting it in the computer, absorbing previous MTBO maps into a geo-referenced whole that now measures 1500 sq.km around a small urban area (pop 400,000). Both MTBO and Rogaine course planners report updates. Events are usually one or the other but some parts can allow choice, as you have.
Sample extracts via links to RouteGadget from
http://waitangi21.ohv.org.nz or go direct to
http://www.routechoice.co.nz and select the "Waitangi" events.