Ok here is my next problem. I hope this thread isnt here yet.

When i started editor (shift+u) and i will place a long barrier i take it (so its "on my mouse") and could place it. Thats not the problem. But how can i turn around it?

Oh ok i have it. Delete post plz

"," and "."

Or the "Rotation" slider bar on the top of the lower left settings panel.

http://en.lfsmanual.net/wiki/Autocross
http://de.lfsmanual.net/wiki/Autocross_Editor

notice my picture in the wiki ^_^