Today I tried again and the problem persisted, but then I used other browser and it downloaded the latest version, so I dig in a little bit more and realized that the download link does not change, is the same every day even though the build is different. So the problem is that chrome (my default web browser) is catching the download so I was always getting the same file I got the really first time.
To solve it is as easy as adding the string "&yymmdd" (where yy is year, mm month and dd day) at the end of the link, a simple parameter that your server will ignore (as it will only look for the FileItemID querystring) and will let the browser know that the link is *different*. I tested this solution by writing this url manually and it works just fine.
Regards,
Carlos.