Do you have the system of the "Moons orbit a fictional planet"?
Sorry, I don't. This was a screenshot I took after some random experimentation. You should be able to come up with something similar by:
- Open up the "Moons, 75 orbiting Earth" simulation (you're already in "Bounce" mode)
- Add a Neptune body
- Shrink the mass on Neptune (and maybe its radius)
- Click "Orbital All"
- Change the color mode to Velocity (I think that's what I used)
Let me know if I can be of any more help.