Thanks for all the assistance from everybody! If anybody can figure out WHY that route wouldn't update, that would be cool. I know it doesn't work, but I still don't know why it didn't work. I set basic way points for the overall route, then drag in via points to clean up the details.
It looks like Tyre is my answer for now.
Fortunately, since Tyre no longer requires the Google account key, I can use it to make the routes work. I set up another one of my old routes with Tyre last night, and it loaded with no issues. Hopefully those results will continue.
The BaseCamp issue didn't happen on ALL of my routes... maybe 1 out of 3 or 4, but the aggravation just isn't worth it. I try setting all new waypoints, using fewer waypoints and more via points, using all way points, using nothing but waypoints... it just doesn't seem to matter with some of these routes. I still get upload fails. Typically, I select key waypoints, create route using selected way points, then shape it with via points on the screen. That's about it.
I will say that in reality, there is NO limit on waypoints and via points. If your route is too big, The device will split your route into 2 (or more) routes. I've seen that many times. I usually redo the two routes so that the start / end points are in logical locations, but one route I put together the other day imported fine, but was large, and it split into 2 routes on import. A couple of the Garmin reps insisted that this couldn't be done. I've done it for years.