I haven't been able to download anything from the download center for FPGAs; I tried with 3 browsers and no luck. I found the issue is actually because of my Ad blocker, disable all extensions just in case and the download will work.
Thank you for sharing your solution!
Another solution that often helps is clearing cache on your browser.
You can also post here and the Intel Community will be able to provide a direct link to download the softwares.