Before creating your composite products, go to the tab General and enable the option Enable plugin features. This will allow you to proceed with the product configuration described on this page.
Through the option AJAX variation threshold, you can define the variation count threshold, after which WooCommerce will load the selected variations via Ajax to prevent the page from overloading.
Finally, if you don’t want to show the quantity of the composite product from the order table, enable the option Remove composite product quantity from order table.