The Media Library menu item should be included as a new schema file in the latest CMSB release. Can you double-check to make sure you've added the new file "/cmsb/data/schema/_media.ini.php" to your site? You may need to update the "uploads.ini.php" schema file as well.

Let me know if that helps!

Thanks,

It seems a silly question, but I cannot find the answer.

Although I have activated the Media Library option, I cannot find the corresponding Media Library button. 

Can anyone give me a hand?

Regards, 

Andreas Lazaris