If your host told you that the smtp url is authsmtp.streamline.net then that is the URL that you will need to use to get the email sent. Do you know if this server requires authentication? The contact form solution pack does not support mail server authentication, you will need to use a mail server that does not require authentication. You should check with your host on this, you should not bring up any scripts, you just need to confirm that this is the URL to use for the mail server and that it does not require authentication. If you can confirm these details and it still will not send when using this address for the server I will open a ticket for you so we can look into this further.