Simple flash video query... possibly

Hi all, I’ve just started playing around with video in flash (I’ve got a straight forward, component based video file running here if anyone’s interested) and there’s a couple of things I’d like to find out more about. There’s a great BBC Food video site [URL=“http://www.bbc.co.uk/food/get_cooking/”]here that’s inspiring me to ask. When I drag the progress bar on their videos the film spins through like a DVD and doesn’t ‘jump’ like my Flash video. Why is this and how can I rectify it? Is it something to do with cue points? Also, their ‘loading’ animation. How do I attach a preloader to an external FLV (or is it an swf that’s loading in with the FLV inside that?).
Thanks kids…