Importing a floor plan from .dwg or .dxf

[Skribbles]

First time user of Visio and I am attempting to make a network diagram. The problem I am having is when I import a cad drawing of a floor plan, all that shows up is the room numbers and staircases. All the walls magically disappear! Is this a problem with
A) the CAD drawing
B) layering of some sort???
C) not converting the drawing
D) Me being a moron
E) Something else

Any help would be greatly appreciated.

Thanx very much

 

[Skribbles]

Got it figured... the drawing was in 3D and apperently visio didn't like it.