Interesting.
What Display Configuration do you have set current?
I see the outline of the Wall Components when drawing Walls with the out-of-the-box (US Imperial) Medium Detail or High Detail Display Configurations set current. I only see the justification line when the Low Detail Display Configuration is set current.
So I am assuming that the Shrink Wrap component is not used when placing Walls, and if your active Display Representation for Walls does not show the Boundary components (either because they are turned off, or the display is By Material, and in the active Display Representation for the assigned Material Definitions, the Plan Linework component is turned off), then you will not get a preview of the components as you place a Wall.
David Koch
AutoCAD Architecture and Revit User
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