So my problem was to download files from temporary links. If you consider Combofix, an util to clean Windows from malware, it's a program updated daily and I want always the last version. But the download link is temporary and always changing, and I don't trust other sites static links. I developed a system to download a list of links, the main idea is to have the list of links in the page and after I go parsing the list to found the correct temporary links. It's dirty but it's working.