Click Preferences in the left hand pane. The Preference page is displayed.
Select Align Names to Legs to display the leg names at the approach road alignment. If left unchecked the names will be displayed horizontally.
Select Calculate Elevations to have AutoCAD Civil 3D 2018 use the specified cross falls and levels to calculate elevations throughout the roundabout. Note that AutoCAD Civil 3D 2018 can calculate elevations even if you are not working in a 3D CAD system.
Select Automatic Linked Entity Updating so that every time the roundabout geometry is changed attached entities like, signs, road markings, alignments, profiles, surfaces and corridors associated with the roundabout are automatically rebuilt after each edit. Consider switching off the option if you are making multiple quick edits to the roundabout, when you switch it back on all attached entities will be updated.