To bjgarner, if you would like to enable file management for each of the instances on the page then you should edit them all. Once edited you should upload the entire HTMLEditor folder to your server.
To eyoung, can you debug your update code to check on the sql that is being used? If you can get the update query to print to the screen you should be able to see any problems if it is missing your page content. Do you have DataAssist? If so you could try making a copy of your page and adding the DataAssist update server behavior to the page to see if that helps you get it updated. If the problem is your ADDT update I'm not sure how you would get it working.