You can update an Etsy order directly from your OpenCart admin to paid or shipped after it has been imported.
You only need to manage an imported order exactly the same as a normal OpenCart order by changing the status of it.
On the menu, click the Orders link.
View the order you want to update
Go to the history tab
Choose the new order status (shipped / paid - or whichever status you have set in the Etsy admin area to match these statuses). Click Add history.
The change will now be uploaded to Etsy.