For the exporting order you need to follow some following steps:
  1.  Need to authenticate company in authentication tab.  
  2.  After authentication you need select account for accounting in account tab e.g. asset account selection for accounting.  
  3.  Need to enable settings for product, customer and order export in basic(general) setting tab.  
  4.  Need to setup order export format and order status selection for order export in advance setting tab.  

Finally you will get a export button on order listing page and also in order edit page.