Example projects

Are there example projects by facepunch - existing games source code e.g. Sausage survivors 2?

There is the testbed aka scenestaging: https://github.com/Facepunch/sbox-scenestaging
In the testbed you can find examples for a lot of features: Doors, wheels, particles and much more! It's also available as a game on S&box.

The Sandbox game is supposed to come soon™, but there are no real templates yet. It's a To-Do on the roadmap.

I think you're looking for something like this? Really useful when you're planning to start from scratch. Hope it helps!

GitHub

GitHub - Facepunch/sandbox: Sandbox mode for s&box

Sandbox mode for s&box. Contribute to Facepunch/sandbox development by creating an account on GitHub.