As of March 2023, Xbox Chaos has been retired. A compiled archive of tutorials and downloads from the site can be found on Archive.org. Assembly is still being supported.
The latest published Assembly build can be found on Github here.
Latest development Assembly builds (potentially unstable, you should keep it separate if you care about automatic updates) can be found on Appveyor here, though these builds only stay up for 30 days, so this link may appear empty at times.