A quick search on the file you referenced indicates that it is an actual zipped file.
I've not used it nor have any association with it so use at your own risk.
Here is where I found info of what is supposed to be in zipped file and how to use it.
Two links on site I found one to download file you referenced and other to link below.
Maybe it will help. Be sure to check files for bugs as I'm not saying this is the best way. I'm only trying to help with info we have at this time.
NOTE: If you are successful I can vouch for the flash tools posted by @raghu_varma
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