Is anyone here familiar with flowplayer?

I've got a technical trouble whereby the flowplayer plays only sound, but doesn't display any video.

Here's a test page:

LINK REMOVED - PROBLEM SOLVED

Right now you can hear the sound but there is no video display.

I have identified the problem to be with the WordPress theme "Mantra" (which I got from this link below) as I've switched it to the default Twenty Eleven theme and the player shows.

WordPress › Mantra « Free WordPress Themes

Thus the problem should lie in the coding of the Theme.

Does anyone know if there is any line I should add or remove in the Theme Editor? Thanks in advance.

Edmund

P.S. I got the flowplayer script from here:

Basics : Flowplayer

I've been using Flowplayer for my WordPress membership sites without problems, just that it didn't pan out correctly this time - and I'm kinda reluctant to change the theme because for one I like it, and affecting over 60+ pages of content doesn't sound nice.