All of the images and contents are loaded already with your composition in this case, so as you sadi they are just merely hidden
Would you happen to know or be able to recommend a tutorial or resource that explains a way to load the content as needed?
actually what ever you make inside edge animate will be define as static element, so anything inside the stage will be load at first !!
you can just prevent loading content on edge animate that you made them as dynamic !!
for example symbols in edge animate can use for later use, so you can create objects as symbol and make them on the stage as the time you want to create them and delete them after you used them, and its not very easy as static elements of course but more secure
you can find in the forum how to create dynamic content within edge animate.