Hi Volker,
I checked your account and it seems like there is a problem with the licensing on our side. There are two activated Telerik platform licenses and I guess this is the problem. I can't fix it myself today and will ask the product and sales teams for assistance the first thing on Monday.
If you want to test NativeScript *today* you can create a new Telerik platform account and send it to me to active NativeScript features on it - let me know and I will assist you.
Best,
Valentin.Stoychev
Telerik
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