prefab_to_folder.py is used to converte the prefab. procthor_to_scene.py is used to converte json in procthor to usd. You need to modify the path of the converted raw assets in the import_asset_new() ...

I was able to make this project compile and run with my unity 2018.2.10f1. I played with the scenes you guys provided. Indeed it is very straightforward to export simple scene which contains cubes, ...