hi @nilabha : This looks really cool. Since most activity around this challenge is here I suggest you post about this in the forums there.
It would also be great if you can add some introduction documentation on how to use your repository and comments on your code.
Have you tried using different observations then the stock observation provided with Flatland? I believe to improve your results using actor critic you need to implement and add new features to your solution. I'm happy to discuss these in the forums with you.