Mark3D

Some times with imported terrains you can get away mostly only using major contours that makes it easier for chief to handle

Have a look at this file see if it is any good, I reduce your sub facia and made your facia larger also a larger over hang on hip walls i added 1" 361955604_GambrelRoofShed Mark edit.plan

Image showing the result, I use a program called formZ that is like sketchup only a bit better i think and it can give you mesh volume and i wonder if it would work if the 2 meshes volumes where compared but never tried it.

I would make 2 terrains one would be existing then convert to symbol then edit existing to proposed and merge with symbol sometimes I give the symbol a semi transparent material so you can see through it in 3d

It sounds like you need to change the render setting in your viewer program

If you can upload your plan file compress if it is big or after compressing it, it is over 14mb dropbox or other cloud share

check this post

Terrain Contours Absolute Elevations vs. Sea Level Elevations - Video | Chief Architect

There is 2 elevation lines that cross the retaining walls near garage entry pull back to the other side of retaining wall that should look better, also turn terrain surface smoothing to low that will hopefully give you a bit more control

No just the one you want to see through second

I could make symbol that i can make in form z if you have sizing details if it is a spiral

See if that is a workable way to do it, there is some missing moldings but if it is good enough just add some molding lines I converted railing to symbols used invisible walls and soffits Also i deleted some stuff as file was to big FloorPlan 2 Mark edit.zip

Try and break the wall and change the wall type

You need to copy the material and adjust