PasswordMaker PHP edition 1.3 has a bug in argument parsing. All arguments in code are checked with isset() function, but code begins with setting all arguments to empty string (''), so isset() always returns true and default values for arguments are not set.
Which means that unless you set all arguments, PasswordMaker returns empty string (because error checking doesn't report anything to the user).
Quick fix is to remove (comment) the empty-string-init line:
//$args = array('alg'=>'md5', 'mpw'=>'', 'url'=>'', 'user'=>'', 'mod'=>'', 'len'=>'', 'charset'=>'', 'pfx'=>'', 'sfx'=>'', LEET=>'');
"Nicer" way would be to replace isset()s with !=''. Also it wouldn't hurt to report errors to the user (if he enters invalid arguments).
PasswordMaker is a great idea, thanks to all developers!