Google have started to silently block http download links if they are embedded in https web pages.Details of this change can be found at https://security.googleblog.com/2020/02/protecting-users-from-insecure_6.html
Depending on how you are viewing your CSD downloads link email, you may find that Chrome will not allow you to start the download by clicking on the link.
The solution is to right-click on a download and copy the hyperlink, then in a new tab paste the link and hit enter. This should start the download as normal. Alternatively, use a diffferent browser where these retrictions do not apply.