If I understand your intent... you want to copy the feature lines into another 3D (or 2d) model or file.
1. reference the 3d model of the corridor to the new file or model
2. use the level display to turn off the levels for the elements you do not wnt to copy
3. use the Merge into master - reference command i.e. Reference Manager > (right click file) Merge into master
HTH