If you facing the problem of running two trains on one track despite putting stations at proper places, here is a brief explanation of the signal system that will help you out.
There are two types of signal systems in the game: the first one is regular rail signal, and the second one is chain rail signal. Both of these signals work in a different way. The function of the regular signal is very simple. It only checks whether there is a train at the next station or not; it doesn’t take into account whether the next signal is a chain or regular. On the other hand, the functioning of chain rail signal is very complex and is very important to understand if you want to run two trains on one track.
The chain rail signal’s primary concern is to identify whether there is a train on the next station, or in other words whether the next signal is red. So in this case, the chain signal will turn red. This situation only happens when there is a single path ahead. If there are multiple paths ahead, the chain rail signal will check whether any path is available. If there are multiple paths, the chain rail signal will show one of three lights: it will turn red if all the paths are unavailable; it will turn green if all the paths are available; it will turn blue if one of two paths is available.
Now the problem is that if your train isn’t moving forward, either there is no path ahead, or there is no chain rail signal to identify the tracks lying ahead. For this purpose, you can set chain rail signals at different intersections that will make the movements of trains smooth and regular.