Max number of waypoints on map??

I just entered a flight plan with 83 waypoints, including the origin and destination.  Only the first 68 waypoints are visible on the map.  However, if I do a Direct-To the 5th waypoint, five more waypoints will show on the map toward the end of the flight plan.  If I do a Direct-To the 15th waypoint, all the remaining 68 waypoints will be seen, but not the first 15.

There is no fixed waypoint limit. There is a limit on storage size however. As an example, a hold in a flight plan is something like 5 bits whereas a waypoint might be only 2 bits. We only have x bits of space available for storing a flight plan. When you go direct to a waypoint in your flight plan it frees up some storage.