It does sound like the likely culprit is a mesh. I hope you have some kind of organization to your 3.45 GB of CC.
1. Take your downloads folder out of the game and stick it on the desktop.
2. Create a folder named Meshes or whatever on the Desktop. As you test the meshes you'll put the ones that appear to be working okay in here.
3. Create a new Downloads folder for the game. If you can create subfolders you can put the Meshes folder in the Downloads folder.
4. Create a Retest folder on the Desktop.
5. Open the Desktop Downloads and use the Windows Explorer Search function to search for mesh. This will open another window with all the file names that have mesh in it.
6. Take 1/2 of the mesh files and put them in the game's Download folder.
7. Try the game, to include proposal.
7a. If everything worked right, these meshes are okay and you can put them in the Meshes folder.
7b. If you crash, you have a bad mesh in with that group. Take 1/2 of those out and put them in the Retest folder. Keep repeating step 7 until the game works right.
8. Now take the other 1/2 and put them in the game's Download folder.
9. Take the other 1/2 out of Desktop Downloads and repeat step 7.
10. If you have some files in Retest, move them to Desktop Download.
11. Repeat steps 6 through 10 until you have identified all the bad meshes.
Once you get down to 10 or 20 meshes, you may want to start putting a couple in at a time to check.