Hey Dave,
Good catch, and thanks for the detailed report. You are right that the address confirmation button did not stand out enough. Looking at it, the "OK" button that validates the address form was using the plain button style, the same one as the "Cancel" button next to it, while the other main buttons of the checkout (the "Next" button, and the "Add a new address" button) already use our highlighted "success" style. So the one button a guest really needs to click was the least visible of the group.
We have changed that for a future release: the address "OK" button now gets the same highlighted style as the other main buttons, so it stands out as the main action of that step.
If you want the exact same thing right now, two ways:
1) The quick, no override way, add a bit of CSS in your template. The button always has the class hikashop_checkout_address_ok_button, so you can target it directly:
.hikashop_checkout_address_ok_button {
background-color: #28a745;
border-color: #28a745;
color: #fff;
font-size: 1.1em;
padding: 10px 22px;
}
.hikashop_checkout_address_ok_button:hover {
background-color: #218838;
border-color: #1e7e34;
}
2) The same class we are adding by default, via a view override. In the HikaShop back-end go to Display, then Views, edit the "checkout / show_block_address" view, find the OK button and add the hikabtn-success class to it:
class="<?php echo $this->config->get('css_button','hikabtn'); ?> hikabtn-success hikashop_checkout_address_ok_button"
With that class the button automatically inherits HikaShop's highlighted button style, no extra CSS needed. From there you can still fine tune it with the CSS above if you want your own colors.