Studio is not behind a membership and never will be. Building, scripting, playtesting and saving your world all work without paying anything, and without an account at all.
A membership is for people who want to publish a lot and keep a shop stocked. If you just want to make things, you already can.
R$ —
Ryx is the Rysics currency. You spend it in the catalog and earn it by making things other people like.
Studio is open right now, free, with no sign-in.