Thanks to the topic Performance Hilfe I take a look to the 3D settings of my graphics card and set them like Florian made the lexikon topic NVIDIA-Grafikkarte für LOTUS optimieren. Then I set my graphic settings in Lotus to balanced, put out the shadows. Then I did a testdrive in Düsseldorf and drive the whole route at night an day on a speed constantly above 45, to see what the map did with the loading of the textures. My FPS are most of the time around 20 (with a fall to 15) and with a few places that have a little longer loading time, it was flawless. I also made a testdrive on Sonnenburg V2 and did the same and drive with a little lower speed, everything was fine the textures are loading perfectly and the most are there when you drive to the next stop of the map (no longer loading times of threes and stops and cars). So now I think this is fine to drive, I will make a few more testdrives the next days and weeks and I will see of this is the same like I had now.
So I'm a happy player now. Let's hope this will be forever