Oh! Ah, I now understand what that weird thing with the chain links and line mean. Awesome. They really didn't explain much.

Here's what should happen:
https://www.youtube.com/watch?v=fKDNibf1S6w

I tried this set up before checking the guides, and it doesn't work for me. The first time I pass over the third switch, it changes the direction, do it never reaches the second loop.