Foohy has finally released his awesome rollercoaster addon!
It is available on the workshop (You need to be logged in to see/subscribe).
If you’re new to the workshop just go to that page - click subscribe - then next time you’re in GMod13 it will automatically download and install the addon. Don’t forget to give it a thumbs up!
You can find out more about it, report bugs and ask questions on the workshop page.