If you are using a Mac you can try following this guide: https://www.youtube.com/watch?v=6--dQQ9U1fs
If you are on Windows you can try using 7Zip to extract the files as that is what I used to create the archive.
If you are still having problems unzipping the archive please contact me as well as letting me know what operating system you are using.
You can take each individual model and scale, move, or duplicate them to create your own custom scene. The models are not limited to being used in a church scene.
In the Blend file go to "File > External Data > Find Missing Files" and choose the textures folder. This will find all of the missing textures within the textures folder.