Hi Eric,

Please add the custom code below. (How to add custom code? ↗):

add_filter( 'wooco_component_product_selected', function ( $selected, $component_product, $component ) {
    if ( isset( $component['qty'] ) && ( $component['qty'] > 0 ) && isset( $component['multiple'] ) && ( $component['multiple'] === 'yes' ) ) {
        $selected = true;
    }
    return $selected;
}, 99, 3 );
add_action( 'wp_footer', function () {
    ?>
    <script type="text/javascript">
      (function($) {
        $(document).on('change', '.wooco_component_product_qty_input', function() {
          var $item = $(this).closest('.wooco_component_product_selection_item');
          if ($item.data('purchasable') === 'yes') {
            if ($(this).val() > 0) {
              if (!$item.hasClass('wooco_item_selected')) {
                $item.trigger('click');
              }
            } else {
              if ($item.hasClass('wooco_item_selected')) {
                $item.trigger('click');
              }
            }
          }
        });
      })(jQuery);
    </script>
    <?php
}, 99 );

Then the products will be selected automatically when the quantity is bigger than zero.

We'll check and implement it soon.

If you are satisfied with our plugin and support, please reward it with a full five-star ★★★★★ rating.
https://wordpress.org/support/plugin/wpc-composite-products/reviews/?filter=5
Thank you in advance! ♥