Orders paid by Google Checkout not Confirmed

When someone places an order and uses Google Checkout to pay, the order status doesn't change to confirmed. How do I set it to do that?

Here are my settings:

Sandbox: No
Server to Server: No
Charge and Ship: Yes
Debug: No
Verified Status: confirmed
Invalid Status: none

NEVERMIND

*dunce hat*

Forgot to set the API callback URL in my Google Checkout configuration O:)

My site doesn't have an SSL certificate so I've been getting emails from Google Checkout saying that the order notification is failing. I tried to change the API callback URL to http:// instead of https:// and selected "Notification Serial Number" under Callback contents in the Google Checkout integration settings (since that option doesn't require HTTPS) but that still doesn't work. How do I fix this?

Does this callback URL have to be something specific? I have an SSL installed for my site, but I'm not clear on how the callback works exactly. I put in an https call back to the user control panel where it shows their orders. Is that correct?

Here is a stupid question .. where do you get the API callback URL ?

It should be simple and intuitive, like maybe a button on the Hikashop google checkout plugin........ but nothing is ever that easy... and the URL for me is no where to be found.

Where is the URL?

Thank you Nicolas
But if you would not have told me personally, how would I have found it on my own?