Model orientation wrong but only while using blendspace graph

Hello Experts!
I am a total noob so I hope my question is not too stupid.
I have a major Problem though and cannot find the answer online. I followed this Blendspace tutorial 7 - Blend Spaces , but used my own Mesh Skeleton and Animation, I made in Blender. This Mesh/Animation works fine if I import it into the editor using Empty Character and chosing my files to fill it. In Blendspace it shows up correctly positioned at first but as soon as I drag my Idle animation into the graph, it rotates everything 90 degrees around the X Axis and the viewport zooms out a few kilometers. Rotating the model at import does have impact on the Empty Character approach, but not in Blendspace.

Where could be the error in my approach?

Ok, I found my error.
It seems that the root bone needs to be vertical…