Sample files won't extract

I am downloading the sample files in the Advanced Storyboarding to work on. Some of the files unzip (extract), while others do not.

Files that downloaded and unzipped correctly:
Efficient Project Creation
Background Layout with Storyboard
Storyboard Revision

Files that would not unzip (extract): Error message: The compressed (zipped) folder is empty.
Project Management
Advanced Panels and Captions
Advanced Drawing
Advanced Input
Library and Templates
3D Storyboard
Advanced Export

Note: Even though it says its empty, I can see the file size of them, so I know they are not empty.

If none of them extracted I would figure the problem was on my end. Can anyone download these successfully?

Thank You!
Alan Mathison