Slider Shop Page

Hello, im currently using BeTheme Farmacy layout, and im having the next issue:

What I need to do? Show Revolution Slider only in Main Shop Page.
Why cant I do it? Changes made editing Shop page via Wordpress are not showing.
Shop URL: https://www.saborsierra.es/shop/

Comment: Im trying to display a revolution slider in the main shop page, and I saw that in Muffin options > Blog, portfolio & shop >  Shop, there is an option to display slider on Main Shop Page, but even if I enable it no slider is showing ¿where do I choose the slider I want to show?. If I attempt to edit the shop page via Wordpress Pages > Shop page, I can choose in the Layout options to display a specific slider, but then these changes are not showing in the page.

This is the only way I made a slider to show on the shop (but its not what I need because its also being shown on single product pages)

add_action('woocommerce_before_main_content','rev_slider_in_shop');
function rev_slider_in_shop() {
 echo do_shortcode( '[rev_slider tienda]' );
 echo "<br><br>";
}


Also an off-topic question: is there a way to put a custom subtitle under the product title in product page?

Thanks you so much