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Placing Order in Ofbiz using Order notification information from Google
Above image shows order detail which is created through Google Checkout process. In this we can see Google order Id near orderId on top menu bar.
Create return
Once order is created after accepting the notification in Ofbiz, If customer wants to return items then we need to perform few more steps for creating return.
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For configuring merchant account following steps needs to be performed. 
Click on Google Checkout button present in the secondary menu section. You will be redirected to the configuration page.
Above screen is used for configuring Merchant information like merchant Id, merchant key etc.
For configuring shipping method we will you the screen present below.
Above screen is used for configure shipping methods for Google Checkout process.