Start the train waiting in the depot at Cornerlock. It will pull into the branch signalled with a staff cabinet, then remain in one train staff after returning to the cabinet.
.sve: https://drive.google.com/file/d/0ByLSSg3gXTz-ZDFOSFdZem9VcTQ/view?usp=sharing
I was not able to reproduce this specific problem, but I have found and fixed a different problem relating to the one train staff cabinet shown by your saved game. Are you able to test to see whether this improves matters?
Thank you for the report.
It seems to work now.
Excellent, thank you for confirming that.