It is possible to create an event based on a batch file you created. Depending on your script, the batch file can or can not accept command line arguments.
Below, is an example of an event based on a bat file:
This event is equivalent with running the script.bat param1 param2 from a command line console, prior or post build time depending on how you created the event.
In case your script doesn't require command line arguments leave the "Arguments" field blank.