Hi Billy,
There are a couple of notes here (sorry but on this "craputer" at work in the office I cannot even get the current snapshot to be imported to SU so I cannot check every word now).
Google used to "encourage" users to hide all edges in the model before uploading. Now AFAIK in the latest SU version it is automated so your imported CAD lineworkwill never show up.
The snapshot and terrain images are never diplayed in GE so whatever you drape on them will not be displayed either (you can use Tom's workaround however).
It seems to me that you are only working with the snapshot and not the (elevated) terrain. Notice that there are two extra layers in SU after importing the snapshot;
the flat
GE Snapshot which is the one you should start working on (and from your decription that is inded the case in your workflow) and which
is turned on by default
AND the
GE Terrain which has the topography features (which you seem to be missing) and which is
turned off by default.
You should also adjust your model to the terrain (with different techniques since it is never 100% accurate).
You can turn on this layer by clicking the checkbox right to it OR by using the "Toggle Terrain" button in the GE Toolbar.