Trying to get at that sweet esxi 6.7 ISO and your manual download button does absolutely nothing? I found https://communities.vmware.com/thread/518378 and since my pfSense DNSBL feed contains PiHole lists I wanted to do some further digging. Running tail -f /var/log/pfblockerng/dnsbl.log while refreshing the download page reveled the following domain block:
Then a grep -r 'tiqcdn' /var/db/pfblockerng/dnsbl/* showed the domain in multiple lists. Add it to the pfSense DNSBL whitelist, reload DNSBL, and refresh the page to get the manual download button to work. Revert after download and you’re all set.