New to this and having problems with countdown timer

I am so new to flash, I do not know what I am doing. I have not programmed since basic and fortran. I tried to download your countdown.zip and winzip states it’s not a good file. I have tried twice. I have my own gif set that I want to use for a countdown timer and so I was hoping to use your code and figure out what to do. Can anyone help me with this?