Hello Stefan

Amelia's Customer (and Employee) Panel log-in is different from any other log-in you have on your site (WordPress log-in, WooCommerce log-in, Memberpress log-in, or any other log-in you can create). At the moment, there is no way to link the two, so your customers have the same password for WooCommerce and Amelia. It is something frequently requested by our customers, and I do hope our developers will add that to the plugin soon, but I don't believe it's going to be any time soon.

I'll forward this to them again, but I'll kindly ask you to add it as a feature suggestion on this page. Features are pushed up on our "to-do" list when there are a lot of customers requesting those features, so having your vote as a customer can be beneficial to this feature being developed sooner.

At the moment, there's no way to include the free option for logged in users.

You would need to create a category which contains all your services, but only at $0 price. Then, you would need to display the booking form [ameliabooking category=5] (for example) on a page where only logged in users have access to (this can be achieved with the membership plugin). So, since only they have access to that page, only they would be able to book free appointments.

That also means that you will need to modify the shortcode on other pages, so the new category (and free services in it) are not shown.