SMTP should be the following,
# Add multiple SMTP servers by separating them with ;
Config::Set('EMAIL_SMTP_SERVERS', 'smtp.gmail.com');
Config::Set('EMAIL_SMTP_PORT', '465');
Config::Set('EMAIL_SMTP_USE_AUTH', true);
Config::Set('EMAIL_SMTP_SECURE', 'ssl'); # must be "ssl" for Google Apps
Config::Set('EMAIL_SMTP_USER', youremailaddress');
Config::Set('EMAIL_SMTP_PASS', 'yourpassword');
Google API key for what?