Musescore.com video export issue

Hello
I was trying to export a score I uploaded to musescore.com into a video, as the option 'Send to YouTube' allows since some time ago; yet I couldn't find the option to transform it into PianoRoll (Synthesia piano tutorial) instead of a standard video (the default plane sheetmusic), as I was able to do barely last year; I tried turning on the PianoRoll view on the score preview of the page before exporting but nothin' ):

I also couldn't find an option to include a custom audio file for the video's audio instead of its default library sound.
Am I doin' it right? Is there something I'm missing, have those options migrated to another section?

Thanks beforehand for the possible help