You've lost me on that - will have to read properly next time

In general guni, if you want to make your life easier, build one track for each direction. Trying to make two trains pass each other on a single line is complex. Use one way signals to determine direction and space them evenly apart (around train length apart) to ensure multiple trains run through fast enough. Where possible try to make the train continue through the station, and not reverse as that will add complications.
Once you get the hang of that you can try the reversing and other stuff for optimizations
