The Reballance.exe is in executableFile folder. Give it a go once... :D
To run this project succesfully in unity editor, it is necessary to download the unity official ml-agent plugins (https://github.com/Unity-Technologies/ml-agents) and to set up the tensorflow environment as instructed here (https://github.com/Unity-Technologies/ml-agents/blob/master/docs/Installation.md)
More about Reinforcement Learning : https://blog.openai.com/openai-baselines-ppo/