I've got it! I think it's because I replaced images that weren't in fact in my Hype document. I replaced them by the ressources' panel because I didn't seen them in my document, but in fact, I replaced non-existing images. That is a part of why I didn't succeed. So, I just deleted all ressources that weren't used and reimport my good images. Also, I checked to be sure all the images' name in the HTML head of my document were the same as the one I imported. And finally, I cleared all the cache, the one of Hype and the one of my browser. I realized that even if I cleared them and close Hype, the only way it shows up correctly it's when I make a refresh in my browser.
Now, my new question is :