This is an unofficial extension built by JimmyBG that lets you use the Leap Motion Controller as an input for games created in YoYo Games' GameMaker.
(YouTube) Leap Motion + GameMaker v2.
So you want to start developing with the Leap Motion Controller? Awesome!
GM Motion caters for all GameMaker users, with 'drag and drop' actions for beginners and GML functions for more experienced users.
You will need GameMaker Studio 1 or 2. Get GameMaker Studio FREE here.
For more details and instructions check out the Getting Started Guide.