I realised that if I do have a flash object and do not include a 'wmode' attribute, I will not be able to overlay HTML because the flash will always play on top. But if I do include a 'wmode:transparent' , the flash object completely disappears in firefox, whereas if I use 'wmode:opaque' , I get a white box in place of the Flash object.
I've looked at many forums - many questions - but somehow everyone's problem gets resolved when they use one of the aforementioned attributes. So....HELP !!!
Note: using either attribute works in IE.