Yep that’s actually the exact one I used. All the installation steps went as expected except for the nginx part.. Could be a wrong entry in the config file, or just something with my setup. Am I supposed to ONLY change the subdomain.domain.com field? Or does anything else need to be modified in there too?

Actually scratch my previous comment.. I just noticed that I followed an older version of that guide by Andre from last year (followed the link from nostr.com on the relays section). Going to try again from scratch with the updated Feb 2023 version in your link!