I´m using the BMW App as a backup and I use gpx format to export from Kurviger and it really works perfect when setting the correct parameter.
Using the Garmin Shaping Point format does not work proper with the BMW App.
Please be so kind an have a look into this threat, that´s maby helpful for you.
Export GPX file to BMW navigator - Route transfer and 3rd party integration - Kurviger Forum