@hans-van-de-ven-mra-master
In the meantime I have asked Sygic. Here is the answer:
Thank you for contacting Sygic.
Unfortunately, importing routes from external sources is not supported from our side in the current Sygic app versions. It is not possible to use downloaded or created route files (e.g. in the .GPX format) nor any 3rd party software for importing routes (e.g. ITN Converter).
You can plan a route online using our own route planner tool and then send it via email to your device which has Sygic GPS Navigation by following the guide we prepared on our help website:
https://help.sygic.com/en/sygic-gps-navigation-for-android/tips-tricks/how-to-use-the-route-planner-tool-on-the-website.
If you have any other question, or need any further assistance, just reply to this message, I’ll be happy to help.
Thank you very much and have a nice day!
Best regards,