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The script you are using assumes that PHP is installed as a module. PHP is installed as a CGI on our servers. Your script should have documentation for how to install it on servers that run PHP as a CGI. This is sometimes referred to as PHP SuExec or SuPHP.
Solution
Instead of adding these directives to your .htaccess file, add them into a file called php.ini and place this file in the same directory that your script runs in. Most often this will be public_html, but in some cases you will install your script in a subdirectory. Wherever your script runs, this is the place for your php.ini file. You will need to drop the "php_flag" and "php_value" prefix. You will also need to put an equals (=) sign between the setting and the value.
For example, if your script recommends these settings in a .htaccess file
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