Tony, thank you for your feedback. I guess I can answer some questions here:
1) Well, it will be hard to provide auto-installable configs for the nginx server, since it doesn't utilises any local files like .htaccess and can't be configured by webserver user (generally). That is why we offer some documentation on our Knowledge Base.
2) Nginx setup articles are on
http://kb.x-cart.com site, not the "devs" one. Try searching for the "nginx" term, it'll show some general articles with nginx sections:
The common configuration is described in
http://kb.x-cart.com/en/general_setup/setting_up_seo-friendly_urls.html and
http://kb.x-cart.com/en/setting_up_x-cart_5_environment/secure_configuration.html. It is sufficient to run X-Cart store (my own dev-installation runs with this config).
Please tell us if you would like to see some deeper insights into nginx configuration.