You shouldn’t have to do any code customization. Our manual approval feature works exactly the way it is explained. When manual approval feature is enabled, a user’s account will be set to “pending” status. This allows the site admin to check the account and then approve the account by setting the status to “active”.
If it isn’t working that way on your site then there is something else conflicting. Maybe you did a customization which is causing some issues. I will jump on your site and take a look. I have sent you an email for it.