Thank you for your contribution
1. Can I put blogspot url ? or subdomain ?
2. I got this error : Warning: curl_setopt() [function.curl-setopt]: CURLOPT_FOLLOWLOCATION cannot be activated when in safe_mode or an open_basedir is set in backlinks.php on line 107
You need to turn off safe mode. You can do this by editing your php.ini file.
And multiple keywords should be ok as they are sent as the title to pingomatic.