Buggy…

I gave it a try with WP 4.1 and it installs without error.
It appears to work but…

1- the settings page goes to wrong folder.
It goes to:

http://www.mydomain.com/wp-admin/admin.php?page=wpn-settings.php

Instead of:

http://www.mydomain.com/subfolder/wp-admin/admin.php?page=wpn-settings.php

2- More severe: Opening Product image in the lightbox stops working with plugin installed.

https://wordpress.org/plugins/woocommerce-product-navigation/