If you have those 4 php files uploaded to the back end of your site, you can go into ShipRush Web and create a new webstore and point it to your Magento v2 environment. It will ask you for the token value set in ShippingZSettings.php.

If you've already done this, please email into support at shiprush dot com with your email address used with ShipRush and we can review your webstore further.

Thank you,
SYSOPS