Complete Web Module's File Transfer Functionality for File Categories and File List

I am looking for a skilled JavaScript and PHP developer to finalize the upload/download feature in a file transfer web module I have been working on, in two different areas, File Category Icons and in uploading and downloading files in the File List itself. The functionality is partially complete, but I need the right person to help me fully operationalize it. The code to add, edit and delete database records, as well as everything needed to login, is all working. The upload ability in File Categories was working previously. We never got the File Upload to work like we wanted, including support for uploading multiple files from a single dialog, each connected to separate records in our database Files table. What Already Works: * All the routing, dialog boxes, backend API stuff is done. * The front-end and back-end work to create records, lookup records, save change and delete records is done. * Security and login stuff is functional and not part of this project. * This is all about the actual file uploads and saving contents using the DMUploader library to finish the upload functionality for this module ([login to view URL]). Key Responsibilities: * Polishing the existing module's upload/download system to perfection. * Enabling it to handle a variety of file types including documents (PDF, DOCX), images (JPG, PNG), and media files (MP3, MP4). Skills & Experience: * Proven expertise in JavaScript and PHP * Experience in developing or working on file transfer systems * Excellent understanding of handling various file types We have a detailed specification attached to the project along with existing source when ready, and we can provide login credentials to an operating version online as well as the previous version implemented separately that we are trying to improve upon. Project also includes bonus milestone options up to 50% of the project amount. YOU MUST READ AND AGREE TO THE TERMS IN THE PROJECT SPECIFICATION TO BE AWARDED THE PROJECT AND BEGIN.