Preloader problem

My problem is one of those REAL bad ones, in so much as the EXACT same code worked yesterday on a different FLA.

I’m using the following preloader on a small movie sequence i’m building, to deliver the streamed status of the movie.

 
onEnterFrame = function()
{
total = Math.round(_root.getBytesTotal()); 
download = Math.round(_root.getBytesLoaded());
 
loaded_txt.text=Math.round((download/total)*100);
 
if (total==download)
{
nextFrame();
}
else 
{
stop();
}
} 

When accessing the html page from my server http://www.ernisystemc.pwp.blueyonder.co.uk/walking_bodge.html I just get a blank screen for the four or five seconds it takes to stream, and then the whole movie hits you in the face, with a really brief glimpse of the preloader just before the real content begins.

Thanx in advance!