We have an Open Cart VQMod Plugin which is programmed to queue invitations when orders are set to complete within Open Cart.
Installation instructions are available from the Reviews.io Dashboard at Company Setup > Automated Review Collection > Open Cart.
Once you have copied the VQ Mod files to your installation you are ready to test that it is working correctly.
A success message will appear at the top of the page where you are expected to be marking orders as complete to notify you that the review invitation has been queued.
The plugin will use the Complete Status which can be set in System > Settings > Option > Complete Status
Within the Reviews.io Dashboard you can go to Invitation > Review Invitations to ensure the invitations have been queued.
Note: If you're using custom templates in OpenCart then custom modifications to the plugin will be required