You probably just need to update your images to use site root relative paths.
Since the edit mode is shown on a page in the admin_cms folder, it won't find images that use a relative path...
for instance if you have content on your home page with <img src="images/test.jpg">
in the admin folder it wouldn't find the image, because that would map to: admin_cms/images/test.jpg
However if your original image used: <img src="/images/test.jpg"> then it could display from both locations.