Hi Cleverson,

#1. To uncheck checkboxes by default, please add the below custom code (How to add custom code?)

add_filter( 'wooco_component_checkbox_checked', 'wooco_component_checkbox_unchecked', 99, 2 );
function wooco_component_checkbox_unchecked( $checked, $component ) {
    if ( $component['optional'] === 'yes' ) {
        return false;
    }
    return $checked;
}

#2. I can help you add a snippet to REPLACE the main product's image with the selected product's image. We can't set a new image based on selected component products. Please watch the screen record video https://www.screencast.com/t/nc7dUOBv

If you want that, please add the below custom code (How to add custom code?)

add_action( 'wp_footer', 'wooco_change_main_image_1' );
function wooco_change_main_image_1() {
    ?>
    <style>
        .woocommerce-product-gallery-new img {
            width: 100%;
            height: auto;
        }
        .wooco_gallery {
            cursor: pointer;
        }
    </style>
    <script type="text/javascript">
      jQuery(document).on('wooco_selected', function(e, selected, selection, component) {
        var img_full = selected.attr('data-imagefull');
        var select = selection.data('select');
        if (select > 0) {
          if (img_full != '') {
            jQuery('.woocommerce-product-gallery:not(.woocommerce-product-gallery-new)').
                addClass('woocommerce-product-gallery-ori').
                hide();
            if (jQuery('.woocommerce-product-gallery-new').length) {
              jQuery('.woocommerce-product-gallery-new .wooco_image').html('<img src="' + img_full + '"/>');
              jQuery('.woocommerce-product-gallery-new').show();
            } else {
              jQuery(
                  '<div class="woocommerce-product-gallery woocommerce-product-gallery--with-images woocommerce-product-gallery--columns-4 images woocommerce-product-gallery-new"><div class="wooco_image"><img src="' +
                  img_full + '"/></div><div class="wooco_gallery">← Back to gallery</div></div>').
                  insertAfter('.woocommerce-product-gallery-ori');
            }
          } else {
            jQuery('.woocommerce-product-gallery-new').hide();
            jQuery('.woocommerce-product-gallery-ori').show();
          }
        }
      });
      jQuery(document).on('click touch', '.wooco_gallery', function() {
        jQuery('.woocommerce-product-gallery-new').hide();
        jQuery('.woocommerce-product-gallery-ori').show();
      });
    </script>
    <?php
}

If this snippet doesn't work for your site. Please give me a composite products link on your site then I can check it then give a new snippet.

Thanks for the link!

Do you mean when choosing component products, these products' images will be appended here https://www.screencast.com/t/xfDJ4xqT instead of completely replacing the main image?

Yes, this snippet doesn't work for checkboxes.

I think a better solution is open the quick view popup for each component product https://www.screencast.com/t/xHsRQyACu9

And the result (screen record video) https://www.screencast.com/t/GNbyBCwrkrj

If you want the price will change based on selections, please choose this option for Pricing https://www.screencast.com/t/GfgyyGLyEWyX

Now, have only issues with the component products' images, right?

If you want something like that https://www.screencast.com/t/nc7dUOBv, please send me your website credentials (wp-admin link, username, password) then I can do that for you. You also can create a dev/staging site with the same configurations then I'll work on it.

We have processed your request and refunded this payment. It's sad to hear that our plugin doesn't meet your requirements.

Hopefully, we could still have your interest and support of other promising plugins on https://wpclever.net

Moreover, kindly check out other stunning free plugins from our WPClever team on http://wpclever.org