So if I plan a track via waypoints, and then navigate it as a route by joining the waypoints together, and setting it to off road mode, I can get in 250 waypoints?
Well, Tracks and Routes are still 2 different things. You'd need to convert one to the other (which is not an option in Mapsource but is easy using the freebie WinGDB3 - supplies some of the bits that Mapsource left out!). But 250 waypoints - yes.
Some limits -
Tracks* 500 points per track, up to 20x.
Routes 250 points per route for most modern Garmins, 125 for a few older ones
or just 50 points if used in Follow Road mode.
And * you can upload
one Track of up to 10,000 points provided it is named
ACTIVE LOGThere are other limitations to be aware of but they're unlikely to come into play on a modern HCx - type unit. The total routepoints limitation varies from model to model but HCx models can go past the 4000 mark easily.