If I insert one of the preloaders in Edge from the preloader library, will this make the whole animation load before playing? What´s the difference from not inserting one? My project will probably be quite heavy when done, will a preloader fix it so that it will run smooth by loading everything before hand?
The purpose of inserting a preloader from Preloader library is just to give an indication to the users that content is getting ready. And when ready, the preloader image is disappears and the real content is visible to users.
The Edge composition automatically preload all the assets used in the composition so that it runs smooth, whether you add preloader from Preloader library or not.