As you can see trains are are not waiting until the shortest way is empty, they are stacking on this stacker waiting till the station/path will be free.
See here: https://forums.factorio.com/viewtopic.php?f=23&t=24232

Train found his path after I remove a red chain signal, but its because its ...

1) But why? Shouldnt train go to the niche if short path are blocked by signals?
No, the pathfinding logic is more complicated than that.
2) No there is all right with tracks, because I tested this path without signals and сhecked that the train can move to the oil station.
So, that the problem ...

Wow! 30 trains... Btw how do u enable all that arrows on the track, and what they are showing?

The train in the north is not proceeding because it is taking the right branch in direction of travel as it is shorter. The track is blocked by the train in the south, that can not reach the oil station because the track in the south west is direction east only.
1) But why? Shouldnt train go to ...

Hey guys I have problems with signals. I checked many guides and tried to make my own rail with 2 trains, but it is not working.

One train stucked at intersection despite of rail chain signal which allowing him to pass, and another one having "no path" issue.

https://s26.postimg.cc/l1mav3e6h ...