well the project appear to be dead and it is time to move on.
in case any of you have similar issues
edit checkout_process.php
and replace
$header .= "POST /cgi-bin/webscr HTTP/1.0\r\n";
$header .= "Content-Type: application/x-www-form-urlencoded\r\n";
$header .= "Content-Length: " . strlen ($req) . "\r\n\r\n";
with
$header .= "POST /cgi-bin/webscr HTTP/1.1\r\n";
$header .= "Content-Length: " . strlen($req) . "\r\n";
$header .= "Content-Type: application/x-www-form-urlencoded\r\n";
$header .= "Host:
www.paypal.com\r\n";
$header .= "Connection: close\r\n\r\n";
and
if (strcmp ($res, "VERIFIED") == 0) {
with
if (strcmp (trim($res), "VERIFIED") == 0) {