Hi again, Dan,
Just wanted to let you know that we’ve released new plugin v1.4.0 today, where I’ve added miles (mi) to the [costs_table] shortcode, so now you can set:
[costs_table prop="distance" table="0-0|25-30|50-50|75-75|100-100" key="AIzaSyC4OkGgzRYLc80yEYzuhU7USYFzwXzzzzz" default_distance="100" units="mi"]
Also, I’ve noticed that you may need to enable “Trigger checkout update” option in “WooCommerce > Settings > Custom Shipping Methods”, so that shipping cost is updated immediately if a customer changes his address on the checkout page.
And last note – if you want to show shipping cost only after customer has entered his address, you may want to enable “Hide shipping costs until an address is entered” option in “WooCommerce > Settings > Shipping > Shipping options”.