I have a Garmin Forerunner 245 and use Mac OS (currently 11.1 Big Sur) with Garmin Connect. I have a workout plan through Runner's Connect, a third party, which syncs with GC for my daily workout data. RC developers say that scheduled workouts on the calendar can now be exported to Garmin as a tcx file. I tried exporting from their end, downloading the file first. But when I tried to upload it to "Workouts," I got a message that the file type wasn't supported. Please help. Thanks.