[3v0]

You dont have the function mksize in your bittorrent.php

function mksize($size)
    {
        static $unit = array('B', 'kB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB');
        $size/=1+(pow(1024,($idx=floor(log($size)/log(1024)))));
        return number_format($size,2)." ".$unit[$idx];
    }

Or change $size = mksize($totallen); to $size = prefixed($totallen);