If you try to import from youtube, you will probably get the error "no element found: line 1, column 0". This is a known issue, and there is a ticket being worked to fix it. In the meantime, here is a possible work around:
1) Start to create the passage (it will still imbed the video, but the text will be "no element found: line 1, column 0")
2) Before saving, in another tab or window google "free, online youtube subtitles downloader" and use it to get the text.
3) Copy it and paste over the "no element found: line 1, column 0".
4) Save.