Preloader Working Irregularly in Browser

Hi,

My application is using preloader to load all images.
It works well in flash environment.

But when i test in server and web browser, with the help of php guys, the preloader loads sometimes say 100%, or 30% or 64%.

When i test in various computers, still the result is the same.

But what is amazing is, the preloader works 100% fine in my system alone.
But in some other system, the preloader works very erratic, using the same URL.

One thing is not clear to me, if there is some problem in the code, why it is loading 100% sometimes.

I have tried by using clear private data, clear cache and all those refresh things. But no use.

Kindly help me as I am on the verge of deadline also I am not a very experienced in AS3.

Thanks in advance.