Trains stuck waiting for exclusive zone

Issue description

I am finding trains are often stuck indefinitely with the state "waiting for exclusive zone"

This seems to occur most often around the track shown in the image I've uploaded. I have also uploaded the save file.

When I run the game loaded from the save file provided, "Train Building Dock off main part of island" gets stuck at the merge coming from the right in the provided image. Initially, it's because it has to wait for another train to pass, but even after that has passed, it does not move, but just waits. I don't know what it is waiting for.

Reproduction steps

Rail expansion.save

Game version and build number

v0.7.5b (b454)

Operating system

Windows

Files not imported: Rail expansion.save

Train Building Dock off main part of island is trying to reserve 2 exclusive zones. Its rejected, because the left track is already occupied by a train. Remove the blue exclusive zones from the junction, so it will only reserve the exclusive zone of its own path.

I doubled the track heading in the direction off the top of this image and that also resolved the issue.

Is there a way for me to see what track a train is trying to reserve?

Thank you.