The strange thing is when I go down to the subpage of "HOCHBAU" then the navigation shows all the subpages.
Can someone help me?

Try something like this (see attachment) and play with the 3 last drop-downs

I tried to change the "Display page" without luke. Since I need the navigation to start in a specific folder it doesn't work ilk that …
Strange is that when I go one level deeper it appears correct and the navigation is a global template. So it should work also from the top …

That's really strange. When I add the level of the navigation like first or second level it is working. But when I told the navigation to start at a specific folder it doesn't work.
Is that a bugg?