File transfer script/upload/download

We need a upload/download file management system (not public) System should be able to 1- Admin users upload files/manage categoies 2- System will assign date uploaded, custom file name. 3- Admin able to add/delete files, arrange in different categories 4- Admin able to generate a download link with a token to send to external user to download the file/files 5- file types support documents/zip/images etc 6- system must be optimized to handle large files 7- simple and nice AJAX interface. 8- Admin is able to add users to upload files and assign permissions to specific categories to upload files. 9- System to arrange files in a nice table format + a simple search, sort function by date/file name/ etc. You can suggest a platform to be used but should be easy to setup and we should be able to handle it as well. a full document/help is provided too by the developer on how to setup the system.