I am trying to download the sms_borer attachment, but when I right click and select save target as it is show a .gif extention. I am unable to download any attachments, zip files.

You are trying to download, not upload.

That link does not exist anymore. I would recommend either googling the application, emailing or private messaging the developer who posted it in that thread two years ago, or looking for another product to serve the same purpose.

You should be able to download others. Some links from before March of 2008 were lost in a BBF server crash.