Hi Wilm,
The Make It Native app is used to test the Native Mobile profile, not the Hybrid phone app. To test the Hybrid profile apps, you will need the Mendix Mobile App. Is it possible that you have the Hybrid profile set up, not the native mobile, but are trying to use the Make it Native app?
The Make it Native version 2.1.0 is intended for Mendix Studio 8.10 and above. If you are indeed trying to run the Native Mobile profile then that is indeed a bug and you should create a support ticket.