Aus irgend einem Grund, stürzt der ME ab, sobald ich bei meinem Bagger mit der Holzschere in den "MODEL" - Reiter wechsle.
This I've also experienced. It crashes with extense/complex models as soon as you select/hover over the meshes. There's nothing wrong with your model meshes, but the exact cause I haven't been able to identify.
A work-around I found is to set the display of ME to the lowest LOD. Then in the model screen you can still see the other lods ;). I guess that if needed you can add an extra LOD with just a cube mesh.