Sorry bother you. My Mac auto unzipped the "ProjectSourceFiles.zip" . It also unzip the "ProjectSourceFiles.unitypackage" file automatically. Therefore, I saw many folders with strange numbers as folder name. Each folder contains files "pathname", "asset" etc.
I use a Mac myself and experience that issue pretty often. Not sure why that happens but I think it's the default program used by Mac that is the culprit. I use "the unarchiver" and I have no issues with that one.
