You have effectively "moved" the existing pages by using mod_rewrite.
I would recommend that you check the pages to make sure that they use absolute for the images, and not relative URLs, such as "../images/image1.gif".
You may need to change the links to the images, or perhaps add another rewrite to "correct" the image URLs.
The above is just a guess. Understand that it is impossible for me to "know all about" your site, how it is set up, and how the scripts work. If you need this fixed quickly, you may want to hire a local expert who can sit down with you and fix your site, and explain the problem to you.