Hello, in order to help you better I need the following information.
Please, send me the information listed here: http://en.savefrom.net/user.php?info=1
Do you download via the extension SaveFrom.net Helper or the website SaveFrom.net?
For the better understanding it'll be great to see a screenshot with the error.

Unfortunately not.

Hello, in order to help you better I need the following information.
Please, send me the information listed here: http://en.savefrom.net/user.php?info=1

For the better understanding it'll be great to see a screenshot with the error.

We have nothing to do with this application.

Hello, please give us more details.

Hello, in order to help you better I need the following information.
Please, send me the information listed here: http://en.savefrom.net/user.php?info=1

Please, give us some more details regarding this problem (no download button,
the button is not clickable, button is calling, but nothing happens).

Unfortunately, the Facebook site itself gives in that quality, the extension cannot download these videos in HD quality.

Hello, thank you for contacting support in Savefrom.Net
This bug is known to us, we will try to fix in the nearby future.

Hello, to download from Dailymotion, install the Savefrom.Net extension:

http://en.savefrom.net/user.php#helper_install