Hello @safeerck,
Yes you can add single song to the cart (I’ve tested your website, and it is working fine), however, as the music store sells intangible products, if you have added a collection to the cart the singles belonging to this collection cannot be added by separated because they are in the cart as part of the collection.
If you cannot download the purchased collection, please, be sure the IPN is enabled in your PayPal account, or your website won’t be notified of the payments and the plugin would not generate the download link, and the notification with the link. Please, don’t confuse the email sent by PayPal with the notification email sent by the plugin.
If you want I check your store’s settings, please, contact me through my personal website with your website’s credentials:
https://wordpress.dwbooster.com/support
Best regards.
