The present invention provides a system, method, and software program for enabling a user to create a customized, high-resolution version of an image (such as artwork) via the Internet. An artist/developer creates an image set comprising one or more base images, as well as any optional image objects that can be added to the base image. The artist/developer uses a script-creation tool to generate a computer-readable script that specifies how to generate an image based on the image set. The script, as well as multiple resolutions of the image set, are stored on a server. When an end user customer desires to customize the image, the server sends the script file and a lower-resolution version of the image set to the user's computer. The user's browser runs the script to create a graphical user interface through which the user can edit the image data in the script file. After the user customizes the image, the modified script file is stored on the server-side. High quality prints can be created from the modified script file and a high-resolution version of the image set.