You disabled this:
$rt = lxshell_output("du", "-sc", $path);
$os = preg_replace("/s+/", ":", $rt);
$ret = explode(":", $os);
$t = $ret[2];
and replaced this with non-working code if Linux installation is installed in different language than English !
exec("du -sc {$path} | grep -i 'total'", $out);
$os = preg_replace("/s+/", ":", $out[0]);
$t = str_replace(":total", "", $os);
Take a look:
[root@nowosci /]# du -sc /home/admin
100544 /home/admin
100544 razem
So there is no word total !
[root@nowosci /]# du -sc /home/admin | grep total
[root@nowosci /]#
That's why Kloxo isn't counting quota properly on so many systems, because we use polish on all of them !