I really wish I could say the differences between two produced videos was something I could easily define, like tearing or graininess or the picture being upside-down.. I guess it just feels like the frames are being assembled in a haphazard way when the back buffer isn't being used, and somehow it makes a difference. I wish I could be more helpful with this.
Here are two more samples, in png format:
Code:
http://h.imagehost.org/view/0056/fox2
http://h.imagehost.org/view/0324/fox3.png
And may I ask why the lock-backbuffer function was omitted from the latest version?