Unusual Firefox / IE Flash Plugin Problem

I hope someone can explain this.

I have created a website for a client that loads around 60 external JPEGs from an XML database. I have made a pretty preloader that hides the pictures that until they are all loaded to ensure they are all visible at once and dont appear sporadically in a messy way.

Now for some reason when I view the website in IE, it works a dream. But when I view it in Firefox, the preloader assumes the images are loaded instantly and reveals them before they are all visible.

Try it for yourself:

Has this happened to anyone else working with a XML Photo Gallery in Flash? Did anyone work it out?

It depresses me immensely because I hate IE and would loathe to have to write “Best viewed in IE” at the the start.

Cheers for any help,