Need a WordPress-PHP expert

Need to change the core functionality of how Wordpress works with attaching images to posts. We have a custom built Wordpress plugin that uses posts to display before and after images of surgeries. Right now the biggest problem we are having is that some cases belong in multiple categories, for example a patient might get liposuction as well as a tummy tuck, so that case should show under both the liposuction and tummy tuck categories. However, Wordpress' default behavior is that if you assign one post to multiple categories, the URL shown in the address bar will be whatever the first category is, rather than the category you are viewing - so if you are in the tummy tuck category, a post that is assigned to two categories might have liposuction in the URL. To get around this, we have started making multiple cases, with just one category assigned to each. However the problem with this is, if you assign existing images to a new post, it removes them from the old one. So we either need to fix the URL to show the current category (i.e. the URL is dynamic and changes based on category), or fix it so that you can assign images in the existing media library to new posts without it removing from the original post (perhaps by duplicating the images). Here is a thread where people discuss how to allow for images to be attached to multiple posts (without removing from the first post): [login to view URL]