Autocad to Sketchup retaining solids

I know this is an old guy question, but I often model things in Autocad and import them into sketchup pro. A few versions ago it was pretty seamless and the Autocad solids remained as solids. If I painted a glass material, the entire object would be transparent.

In the last few versions, I have had to explode everything twice and break the model into individual surfaces to apply a transparent texture to. I also have to apply it to every single face. Which can be tedious. Is there any way to import a CAD model so it remains as a series of solids?

As far as I know SU doesn’t use “solids”…correct?

Correct and not correct. SU is a surface modeller so it doesn’t do real solids. However, a group or component that forms a “watertight” volume (every edge borders two faces, not more or less) is seen by SketchUp as a “solid” so that its volume can be calculated and it can be manipulated with the “solid tools”.

Well not a solid as other 3D programs see them.