I created an instance on Amazon Web Services using Bitnami for a Wordpress site. I've been able to customize the site using WP widgets and plugins, but I can't use the Editor to edit page-title.php or other pages: "You need to make this file writable before you can save your changes. See the Codex for more information."
I haven't been able to figure out how to get myself write access to these files, partly because I don't understand where these permissions are set or how to alter them. Compounding this (I think), I have built our website on BitNami WordPress 3.4.2-1, but I can't seem to Manage my Bitnami account (I'm assuming I have one).