https://pioneerspacesim.net/forum/viewforum.php?f=3
Currently I can't register by myself: "New user registrations DISABLED (for now, due to spam)" so I'm trying to contact one of the site owners as they say here: "if a _HUMAN_ wants to register they now have to contact us on IRC, email, github, SpaceSsimCentral, twitter, or wherever"
I haven't tried to register/allow a user myself, so I'm just posting about it on IRC to hopefully help you out.
Sorry, for some reason I didn't noticed this thread. I'd say you come by IRC when you are around, and we'll open up the reg. Sadly if we keep it open for long time, spambots do get to it. 🙁 We have to fix that.