The ShipStation Plugin has been updated to v1.06. All features have been migrated to all Nop versions of the plugins. See the install guide in the zip file for more information. A reward point issue has also been resolved. This is when an orders is paid in full with just reward points.
You can download the updated plugin by clicking on your email address above then clicking Downloadable products in the MyAccount Screen. Click details to see change list. Be sure to go into the configuration screen set the new options and save the changes.