Highlands and the Roads

The Roads are having problems descending from the Highlands.
When creating a straight path, the roads max height is not high enough.
When there is a slope down, the roads max descending angle is not large enough.

This resource patch was the only one with a slope to create a switch-back.
All the other Highlands with resources only have cliffs.

You are certainly meant to create switchbacks. The terrain generator might not be smart enough yet to give you enough space all of the time though.