jQuery Plugin: http://plugins.jquery.com/project/autosave

I've been trying for 3days to get this plugin to work, I've contacted the developers and no response. the demo on the site seems to work with a json output but the downloaded code & example does not work. I'm trying to get it to work with PHP as the backend and nothing. The instructions are very vague like a lot of jquery plugins. Are there any developers or experience jquery plugin users that can assist with telling me how to get this plugin to work correctly?

thanks in advance