Linking Lumin SDK to Unity

Hello All,
Posting here because I have a issue setting up the Lumin SDK with Unity. I can't browse the Lumin SDK from the External Tools in the Unity Preferences, the option does not show.
So I can't select the Lumin Platform from the Build Settings (it doesn't show neither)

https://ibb.co/ySm15ks (Screenshot)

I tried (twice! with Unity 2019.2 & 2019.3) to follow the steps as described on ML website (https://developer.magicleap.com/en-us/learn/guides/unity-setup) but can't figure out what I'm missing...

I can perfectly run the demo scenes from the ML Examples, even with Zero Iteration running from my device. But can't manage to add the SDK to actually build these apps.
What am I missing?
Thank you.

 

Oh! And of course I've installed the Lumin OS modules for both version (Unity 2019.2 & 2019.3). Otherwise it wouldn't be fun.

Lumin OS Pic

 

Me too... can't find the SDK slot.

 

you need to go to 1) Edit-Preferences
2)External Tools
3) Scroll down to the middle of the page and you will see a browse field you can link the SDK to.

 

The Android SDK Tools installed with Unity are there at Preferences - External Tools. But I get always ArgumentException: File Includ/ml-platform.h not found and in the project settings under Magic Leap- Manifest Settings "Cannot find the Lumin SDK. Please spec the path to the lumin sdk in the editor preferences. When I go to Project Settings -Editor, I do not find any information about the lumin sdk. I loaded down Unity for 4 times and have on AR Foundation always the same problems. May be, Unity is not such a good platform for AR-Games ? If someone can help, I would be happy about.

 

I have given it up with AR-Foundation. Seems to be not ready for making solid games.