Due to the Unity Asset Store not allowing a batch file to be included in the asset, the following changes need to be manually performed in order to use the convenience batch files provided for starting the game as a server or client from command line options:
1. rename Start_SERVER_BAT.txt to Start_SERVER.bat
2. rename Start_CLIENT_BAT.txt to Start_CLIENT.bat

After that, you can use those files on Windows to automatically start the game executable as either a server or a client.