The EventManager is a tool for ShootMania I created a few years ago. It allows mappers to completely customize the games behaviour depending on their map. This enabled you to, for example, play MediaTracker clips when entering a specific area or changing the players weapon when he presses a key.
The tool was used by MCYCShadow in his horror map Paranoia. You can take a look at it here (YouTube):
The project is abandoned because I lost interest in it when the ShootMania playerbase started to die out, but it is kind of continued in form of the Godot Event Manager which aims to provide a similar user experience to Godot map makers.