You will find the cutscene editor at the main menu "WIndows" dropdownlist. To use a cutscene in the game you need two folders in your map directory. A cutscene folder this folder will create automatically if you save your map and a camera folder you have to create by your own, see picture below. In the cutscene folder are all the .XML files the PlugInBasedEditor will use and which you can edit in the cutscene editor. In the camera folder you have to copy your final .CS file which you can directly activated in your script with an action command.