To activate shaders on Toribash,
- Open up Toribash
- Click setup
- Click options
- Tick shaders like this
- Click ok
- There you go, you should now have shaders!
If that doesn't work, you probably don't have a good enough video card or should update your graphics card drivers.
---
If you want to change custom background shaders, type
/lws shadername.inc in the chatbox. You can see all shader names under \toribash\data\shader