Manuel,
Could you be a bit more specific about what is not working with the Storefront Powerpack? I currently have this installed on my dev site with WC Vendors, WC Vendors Pro and the Storefornt theme (of course) and it is working fine, as far as I can tell.
Please give me a few more specifics.
Also, please share your WooCommerce System Status with your reply (wp admin > woocommerce > system status > get system report)
