I'm having the same thing happen to me. I'd be interested in why SH3D creates this duplicate folder containing all other duplicated folders and files inside of it, and why - when deleted - SH3D won't load.

Edit 1: Puybaret - I can make my 70 MB file available on one of my websites if you'd like to have a look at it.
The folder with more folders inside is about 25 MB.
I zipped it up using 7Zip. As a zip file it's about 30.5 MB. As a 7z file it's about 19 MB.

Just let me know if you'd like to take a look at it, to try and figure out what's going on, and I'll upload it and give you a link.