Ok this mod does work. I am finding the issues to be that the user is not reading the instructions correctly and not setting the user database to threads and thus is not pulling from the threads user table. there are specific settings to make it work with each forums scripts. In general in the config-inc.php
make sure
// Path to your PhotoPost installation - no end slashes
$PP_PATH = "";
// PhotoPost database host address, or leave as localhost
$host="localhost";
$database="yourphotopostdatabase";
$mysql_user="yourphotopostdbuser";
$mysql_password="yourphotopostdbpassword";
$pp_db_prefix = "yourphotopostdbprefix(pp_,w3t_,etc";
// User database host address, or leave as localhost
$host_bb="localhost";
$database_bb="yourthreadsdatabase";
$user_bb="yourthreadsdbuser";
$password_bb="yourthreadsdbpassword";
and in your photopost control panel under edit options make sure User Registration System is set to threads