Main video won't download intact

[schuhplattler]

I encountered a bad situation while downloading from Youtube

1. I had only one item streaming, and even though I had filtered the downloads to audio and video only, I got dozens of items listed on the Media Tools window. I deselected all except the first five mp4's and the first mp3. Download failed on all except the mp3 and the first three mp4's.

No MP3 and only one MP4 played in Windows' "Movies and TV" program - without audio. No video played in Windows Media Player. Nothing, audio or video, played in Power Director 10, so I could not put audio and video together myself.
The youtube video intended is https://www.youtube.com/watch?v=w8Gxs6BWK2s&list=RDw8Gxs6BWK2s