You need a windows PC with a windows operating system and .net framword 3.5 installed in order to run the software.
No, you need a windows PC.
You can use proxies. The software supports proxies. In case there are videos blocked in your country you can use a proxy and download them.
How To Use The Fooja?
With the feature "Search Videos" you can search and find videos @ youtube and dailymotion by keywords.

For facebook you can add the url of a fanpage and get a list of all videos of the page and download them!

General Questions
You are not allowed to download videos from any supported host for commercial use. You are not allowed to download copyrighted videos. It is for personal use ONLY! For backup of your own videos or if you want to create your own video you might use parts of other videos under the fair use law - 17 U.S. Code Paragraph 107 - Limitations on exclusive rights: Fair use -
No, we will not save anything.
Yes, Fooja can encode a youtube video into mp3 files. Thats works for youtube videos only. A special codec is needed. If fooja doesn't find it on your pc, you can approve the download of the codec. You can find the codec here when you allowed Fooja to download: /Documents/ffmpeg
Make sure that all videos are public. Specially for facebook, you have to watch the video without log-in to your account. Make sure that you can watch the Youtube video in your country. Some videos might be blocked. Those videos you can't download.
Yes you can. Please use the Search Videos feature. There you have to add your login details and the facebook page url.
After payment was successfull, you get access to (if you paid via paypal). Please login and access your purchase. That will lead you to your license key. Beside that you get an email with your license key.

Yes, just close the Fooja and you will be asked to shutdown the Fooja or to run the downloads in the background.