Railbuster is a GhostBuster theme of roller coaster map made for Minecraft.
So Railbuster is a Ghost Buster movie theme map. It has almost every single building that is available in the movie.
The way to play this map is to ride the cart and then follow the path.
From the footage of youtube trailer, it seems that you can choose which path your cart should go.
Do take note tho that this is only playable for one time. If you wanted to play another game, you need to delete the save map and extract new from the zip file again.
Map is only playable on 1.12.2