1) Always post the command line used, or log file line two, so we know what the
site is, what your settings were, etc.

2) Did you use the near flag (get non-html files related) so you get ALL the
js files no matter where stored?
3) Did you use extended parsing to see if it could find embedded urls in the
js?
> the download was incomplete, the video
> and sound files haven't been there.

There are no videos OR sound urls on that page so HTT can't get them.
Most video sites (youtube) use a .swf file to play them just like this one
does for the audio. It is not the browser that gets the media, it's the swf.
HTT downloads the swf just fine but in a mirror the swf tries to play the
media from the source site, which is your machine in the mirror and those
files do not exist. So you get nothing.