I usually have great success in not needing rendering. I take all of my clips and make them Apple ProRes 422 @29.97fps and everything works. The clip that defines the characteristics of the sequence ...
I have a .MOV video -created with Final Cut Pro 7 - which I'm converting to .flv using FFMPEG. I'm very happy about the quality and the size of the output file, but whenever I have fade in/out ...