The track design evolved a bit over the past few days, it now also includes a bridge and a narrow connecting road. I'll have to experiment with the bridge in order for the cars to be able to climb it (maybe someone has experiences with bridges they want to share).
The design will probably be stowed away for some time before I start building anything, as I'm quite busy now. I might change the design later on, maybe I'll include some kind of a pit somewhere.
You can find the newer design at
http://anthony.liekens.net/track.pdf, it's a PDF at scale 1:5 (I'm working in centimeters).