If you're going to rename the folder structure for UDM4, you'll need to find a statement in the udm-custom file that looks something like this:
Code:
//path to images folder
um.baseSRC = "/udm-resources/";
and change it to this:
Code:
//path to images folder
um.baseSRC = "/resources/";
If that doesn't fix it, put it back the way it was and change your UDM directory structure to match the example code. One of these two things should work for you. If not, post a link to your site so we can have a closer look at the problem.