1- FFMEG-PHP You need to contact the server admin to fix this
2- This may be the convert erro.You can findout the details through our forum
3- If error with FFMEG-PHP can't can't create thumbnail, also please check the permission of "thumb" (777)
4. In admin area you can enable auto approve.
5,6- As depend on the size of the video and network speed.
7- For youtube import function you need to PHP5