Steps to install mosCommerce (Linux)
To make this install, as well as many others easier, I have added users that edit files to the web server group and set the permissions to group writable owned by the web server user and the web server group.
1. Download the archive (mosCommerce_v1.0.4_beta.zip) and place it in the root directory of the Joomla! installation.
2. Unzip the archive and set the ownership of the directory and files to web server and web server group.
3. Add the following line to your .htaccess file:
php_value "register_globals" "1"
4. Open http://your.website.url/joomla_dir/install_mosCommerce in a web browser and select Custom Installation.
5. Step through the installation to fit your needs. During the installation of the Administrative & Public Resources and Configuration files, I sometimes get an error creating the Administrative Configuration file. Clicking Back and retrying normally fixes this problem.
Post Installation
1. Edit administrator/components/com_oscommerce/includes/classes/upload.php and delete the line that reads $this = null (line 31).
2. Edit administrator/components/com_oscommerce/modules.php and replace $PHP_SELF with $_SERVER['PHP_SELF'] (line 77 twice, line 129 twice).