Pretty sure the issue is on your end. I also tested FF and Chrome, and I'm definitely not sitting next to my server... I can also confirm, through the server logs, that other people do manage to download the file.
Clear your cache maybe? As far as the server is concerned, all I'm seeing are nice 200 HTTP response codes for BETA download requests, which means success. So whatever it is, it has to be on the client's side. And the only weird stuff I'm seeing in the error logs are some [ssl:error] Hostname rufus.akeo.ie provided via SNI, but no hostname provided in HTTP request messages, but these look like stuff generated from people trying to probe the server for SSL vulnerabilities, and if your issue had to do with SSL, you wouldn't be able to access any content at all. What happens if you try the http site instead of https?
Threat was detected upon access to web by the application NOD32 doesn't like this specific beta, never had problems with any other the previous final or beta versions
It's a pretty straight forward tool. If you hover over the option it tells you what it is/does anyway...
No its not, but I figured it out. If you use it for the first time, and you want a bootable USB stick, the the first impulse is to install rufus on the usb stick.... I have written this here many times over the years: People here too often give instructions that can ONLY be understood by people already knowing how it will work! You have to talk to a person who doe NOT know... which by the way happens to be the only reason why others ask.