You can simply add “https://gdl.graphisoft.com/forums/feed” to any RSS readers, and it works.
Aha! Thank you Gergely!
One request for a tweak to the RSS feed. Right now, the original post in a thread is titled, say, “Thread Name” and subsequent ones are titled “Reply to: Thread Name”. This seems to prevent grouping by subject in the feed reader (in my case, Thunderbird). Is it possible to eliminate this “Reply to:”?