try following

1. Find a video on youtube.com or any video sharing site.
2. Copy that page's URL.
3. Visit: http://youthtoob.com/media/admin/
4. Login Username: xxxxx - Password: xxxxx
5. Delete content of templates_c/debug.txt
6. Go to: Video Processing > Import Video
7. Check the status of the video.
8. Run cron Job -> http://youthtoob.com/media/cron.php (this will download the video)
9. Check the status, it will say download finished.
10. Run cron Job -> http://youthtoob.com/media/cron.php (this will process the video)

If you have problem, paste content of the debug.txt file.

If the file is not getting downloaded, it can be problem with firewall.

Try downloading a video from another site and see if the video get downloaded.