There is no installation required. Order Export Pro is included in the interface of Store Commander. If you have a Solo+ or MultiStore+ plan, the tool is accessible from the Orders menu > CSV Export. If you just changed your subscription plan, you might need to update your Sc, via Help > Update Store Commander menu.
You can indeed test the module by creating a demo of a virtual shop from this page. Open the tool via the Orders menu of Store Commander interface.
Order Export Pro is included in our Solo+, MultiStore+.
Yes of course, contact our support team using the contact form.
By default, only PrestaShop administrators can access the module. However, you can set permissions on each employee in Sc user permissions that you can find under Tools > Security > User Permissions in your Sc interface.