How to implement MixedReality-ToolKit into an existing HoloLens project?

I am extending the VideoCaptureExample for Hololens in Unity 2017.4.21f from this project: https://github.com/VulcanTechnologies/HoloLensCameraStream

Now I have to control the ScrollView and Buttons from my Canvas so I need the Gaze-Function from the MRTK. As soon as I try to implement the unitypackage from this page: https://github.com/Microsoft/MixedRealityToolkit-Unity/releases for 2017.4.2.0 it shows me many C++ Exceptions while i didn't even use anything from that package:

Exception thrown at 0x76EDF2B2 (KernelBase.dll) in HoloLensVideoCaptureExample.exe: WinRT originate error - 0x80131534 : 'System.TypeInitializationException: The type initializer for 'WinRTBridge.WinRTBridge' threw an exception. ---> System.TypeInitializationException: The type initializer for 'WinRTBridge.TypeInformation' threw an exception. ---> System.IO.FileNotFoundException: Could not load file or assembly 'GLTFSerializationUWP, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.
   at UnityEngineInternal.BootstrapHelpers.FillTypeMaps0(Dictionary`2 , List`1 )
   at UnityEng'.
Exception thrown at 0x76EDF2B2 (KernelBase.dll) in HoloLensVideoCaptureExample.exe: WinRT originate error - 0x80131534 : 'System.TypeInitializationException: The type initializer for 'WinRTBridge.WinRTBridge' threw an exception. ---> System.TypeInitializationException: The type initializer for 'WinRTBridge.TypeInformation' threw an exception. ---> System.IO.FileNotFoundException: Could not load file or assembly 'GLTFSerializationUWP, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.
   at UnityEngineInternal.BootstrapHelpers.FillTypeMaps0(Dictionary`2 , List`1 )
   at UnityEng'.
Exception thrown at 0x76EDF2B2 in HoloLensVideoCaptureExample.exe: Microsoft C++ exception: Platform::COMException ^ at memory location 0x04EFE2F8. HRESULT:0x80131534 The text associated with this error code could not be found.
WinRT-Informationen: System.TypeInitializationException: The type initializer for 'WinRTBridge.WinRTBridge' threw an exception. ---> System.TypeInitializationException: The type initializer for 'WinRTBridge.TypeInformation' threw an exception. ---> System.IO.FileNotFoundException: Could not load file or assembly 'GLTFSerializationUWP, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.
   at UnityEngineInternal.BootstrapHelpers.FillTypeMaps0(Dictionary`2 , List`1 )
   at UnityEng

I have already tried to check the Player Settings and took a research about it and I'm really stuck at this problem. Here are my Player Settings from Unity:

I just took that version of MRTK and latest HoloLensCameraStream source. Running just the HoloLensCameraStream example produced some C++ TypeLoadExceptions; adding the MRTK 2017.4.2.0 didn't increase them nor did I see the GLTFSerializationUWP related typeload. On the contrary I did see in the output that GLTFSerializationUWP was loaded successfully, as it's now included in your project as part of including MRTK.

Two options:

• Generate a fresh UWP build from Unity into an empty folder
• Try updating to a newer MRTK that no longer has the reference to GLTFSerializationUWP.dll

Hope that helps!