Update Records not Working

I’ve built and re-built an update records page at least five times, closely following the DMX tutorial. But I just cannot get the update form to work by populating when I click on one of the repeat record rows. It opens displaying the field names but doesn’t display other records when clicked on in the repeat table nor does the ‘Save’ button work. Please see my testpage to review and let me know what I’ve missed or messed up.