I run a paid membership site (Php, mysql), where I provide training through videos. I allow some members to download the videos for viewing offline.
These videos are created using Camtasia Studio 7, and are using Flash for table of contents on the left side, and the presenter video as well as the powerpoint slides. Videos are hosted on Amazon AWS S3 cloud.

The way camtasia generates it, each video is in its own folder. The total size of all videos is about 3GB, and there are over 60 video lessons.

My questions are
1. How do I allow people to view the videos with flash content offline. They will need a flash viewer, and or download of the entire directory, and all the 60+ directories. Is there any better way? How to make it easy to download/share this content with them with ease.

2. I want to protect the content, so that those who have not purchased the download option can not see the URL of the videos, and are not able to download them off S3.

3. I am currently generating MP4 files so that they are visible on as many devices as possible, and the Camtasia Flash generator for Table of contents etc. Is there any better format or better way to do this?

Please advice.