[AS3] Progressive Flash Embedding with transparency

Hi, I'm having some problems with flash video - I have a video sequence which is rendered as flv with transparency, It has been embedded into the swf previously and the transparency works flawlessly, however when I try to convert it to a progressively downloaded video with a player I get a black background..

Anyone know how I can combat this?

I dont want the user to be able to control the video or anything, I just want it to load externally so that the flash page opens up faster.

Is there a way I can simply point the movie clip to an external flv and tell it to start playing/downloading it without using a player control?

Kind Regards,

Pete