I have uploaded a couple of tutorial videos in youtube.
In my winforms application (by using the AxShockwaveFlash object) i reproduce the selected video by the user.
AxShockwaveFlash1.LoadMovie(http://www.youtube ..video1)
Here comes the story.
The first time the user selects a video, reproduction works like a charm.
When the user selects to see the second video AxShockwaveFlash1.LoadMovie(http://www.youtube ..video2)
the ShockwaveFlash continues the reproduction of the first selection