Routes & tracks sync but I received an error that courses cannot sync unless I update my 955. Problem is: the 955 is updated to 14.20. Apps are updated as well.
Anyone else with this issue?

Routes & tracks sync but I received an error that courses cannot sync unless I update my 955. Problem is: the 955 is updated to 14.20. Apps are updated as well.
Anyone else with this issue?

Yes, same issue. Near as I can tell Garmin hasn't actually implemented compatibility despite suggesting the two are compatible on the app and what Garmin's website states: https://support.garmin.com/en-US/?faq=TBvOwgGAX06QrerRO1LHUA
In fact, I remember spending a lot of time with Garmin Explore and my 945 and trying to figure out how to sync things back and forth. Garmin Explore is definately not intuitive. And, yes, I never did get courses to sync to my 945.
The way to get a course on Garmin Explore and sync it to your Forerunner is to click on the . . . then 'copy as track'. Make sure you add it to the correct Collection that you are syncing and then it will show up. Seems convoluted. It would be easier if it would just sync the route over.