Ok as far as I know it has nothing to do with SQL entries.

It's mainly to do with incorrectly merging files and the placement of files.

Make sure your "includes/templates/YOUR_TEMPLATE/modules" directory has the original file "create_account.php" from the actual mod. Just override what you have on your server. I know! I know!, it sounds crazy but it works!

Also make sure "create_account.php" is also in your "includes/templates/template_default/modules" directory as well.

now it should work with 1.3.9h.