Civil 3D 2014 custom subassembly : Double drainage broken back

2017.01.11 link update

With this subassembly it is possible to enter a double drainage broken back ending to axis or earthworks level or to a user selected offset or to an earthworks slope.
Drainage grade minimum set to 4%.
Inside and outside endings can be NJB (or similar) horizontal level with slope, earthworks slope or user selected distance from asphalt limit line.
Drainage backs, asphalt limit lines, earthwork hinges, NJB level hinges and point on earthwork slopes can be entered numerically or by offset target.

NJB inside, earthworks and drainage cut to axis

Steep cut slope outside, drainage ends to it

Same case inside but grade is to steep so there is a drainage-earthwork levels intersection.

Fill slope outside.

Same case inside but no axis cut.

Outside end to user selected offset (eg retaining wall)

Same case with above but reversed grade

Same case with above but limited to axis

Double drainage broken back