Having Trouble Cleaning Up dwg File Before it is Imported Into Sketchup 2022

I am having so much trouble getting my AutoCAD file cleaned up enough so it is the easiest to work with in SketchUp as possible. I am freaking out at this point because I only have about a week left to work on my project. My college instructor moved all of my layers to layer 0 in AutoCAD while cleaning it up. She removed almost all of my extra layers and helped me out a lot but somehow a lot of them showed up again and I have no idea why or how to get rid of them. I have used the purge all command until I can no longer purge anything out. I have used the flatten command. I have also used the overkill command. Every time I do go to import my file into SketchUp it still says I have a ridiculous amount of stuff in my AutoCAD file that should be removed. I am not sure what else I should do. I already attempted working on the SketchUp file, but it has so many issues going on I think at this point my best option is to go back and clean up the AutoCAD file more. I know something is off with my file when it is in SketchUp because whenever I try to “explode” my file after it is imported, the program always crashes every time. I will include my AutoCAD file if it will allow me to include it. I am pretty new to using both AutoCAD and SketchUp. This is the largest issue I have had to navigate so far.

project3updated-SarahBarta_autocad.dwg (790.1 KB)

sarahb.skp (599.7 KB)
This is what I got. I had no difficulty exploding. There were some extra edges and faces outside the actual map area, I deleted those.
If you want to give it still a new go, change the width of your polylines in AutoCad to 0. The importer imports the width as two parallel edges.

Thank you so much for your assistance! I am not sure why SketchUp kept crashing every time I tried to explode the base map. I tried on multiple computers and kept having the same issue. Was there a certain command that you used to find the extra edges and faces outside the map area?

I know that this is not related to the initial question, but it is regarding SketchUp. Right now I am unable to use the push/pull tool for the majority of the base map. Is there a way to turn the background of the base map grey again in SketchUp and then fill out the map piece by piece with the pencil tool? I need to change the elevation of pretty much every component on the map, but I have no idea what steps to take next.

The background is a style setting. Open the styles panel and edit the active style by clicking it to select, then clicking the edit tab. The background is in the tab with the icon of a little cube sitting on the brown ground. You can set the color to whatever you like.

You can only pushpull a SketchUp face, so you will need to determine why faces are not forming (usually either gaps in the perimeter or small spurious edges protruding into the area) and draw edges to close the gaps or erase the extras. With, e.g., a brown background it should be obvious when a face forms, as the face will be colored either white (front side) or gray-blue (back side) depending on which way it is oriented.

That is because mostly there are no faces in the imported map, only edges. Faces will form if you redraw an edge that is part of a closed coplanar loop or draw an edge that closes an open coplanar string of edges.