I am testing your plugin and I found a bug. When I chose bank transfer as only one payment gateway for DefaultAPGShipping it affects all other shipping classes (default woocommerce classes and aditional APG classes too). So, it gives only bank transfer choice during checkout, however COD is enabled too. If I set ALL ENABLED PAYMENTS for DefaultAPGShipping and bank transfer only for aditional APG class it has no effect(all payment gateways are shown during checkout).
Please help. Thank you.
Btw. great plugin.