I share both, internalized geometry and GH component line.
After I’ve read your response, it looks like I described my issue in unclear way.
To clarify the statement of mine above, I seek to create a surface from curves (polylines*) in green (as shown in screen capture above) , which intersect a mesh (made from terrain curves, which are in red) or extract a mesh detail from existing one along intersecting curves in green.
If your provided component line solves exact issue, then I’m sorry for unnecessary response (I have no access to check your component line at this moment).