VuMark not detected Hololens2

Hi everyone!

For my bachelorthesis I am working with the Hololens2 and Vuforias VuMarks with Unity. I am currently simply trying to detect a Vumark and if I detect it I want to show a Cube. The problem is the VuMark does not get detected (since I see no cube) and I really don't know where the problem could be and I am really frustated. Here is my approach:

1.) I am using the example Vumarks (Chateau / MortonTuxedos) SVG files. I uploaded them in the Database, added the correct ID (for Morton Tuxedos for example "1111") and afterwards I downloaded them as PNG and printed them in the correct width I entered by uploading. I tried both example VuMarks seperatly with no success.

2.) I set up an AR camera. I think the AR camera and my setup works, because I tried implementing an ImageTarget to see if my setup is correct, and the Imagetarget always gets detected without a problem and I always see the child element. I also already set the "Max simultaneous tracked objects/images" to 5 just in case this could be the problem -> it was not. 

3.) I created a VuMark instance, added the right Database and template. I created a simple 3D cube object and moved it as a child from VuMark. I already tried it just with that setting -> did not work. Nextly I added the cube to the Default Observe Event handler to the OnTargetFound() and if it is found I enable the .SetActive() flag. -> did also not work. I also tried to "create" my own Default Ovserve Event handler, since it is mentioned in the api, and copy pasted the default observe event handler in a new class and added a Gameobject, which I set Active in the OnTargetFound Method, but it also does not work.

I also tried implementing a lot of tutorials/the official Vuforia example but they all did not work since I am using 10.3. I also tried (since I am not quite sure if I need a "VuMarkHandler" Object) to copy that from the official Vuforia example to my project, but after compiling I get alot of errors since it does not find the VuMarkTarget (but as far as I know from my research this is only for the engine 9., correct me If I am wrong).

The attachment shows my setup, which has a simple cube which is always displayed (so i know my holograms etc. work) and the VuMark.

I am really looking forward for some help since I am stuck with this problem for over 2 weeks and I don't know where the problem could be.

Thanks!