If you're looking to manage your extensions or redirects without messing with your .htaccess file, look no further. We recently added two features to the Hosting Control Center that help to automate this process. In both cases, if an .htaccess file already exists, these managers will simply add the new details to the existing file.
The Extension Manager
Edit the current extensions in your account or create your own custom extensions. It allows users to specify which application (PHP, for instance) handles certain file extensions (.php5, for instance). Located under 'Settings' in the Hosting Control Center for more details see the following help article.