DOTonPAPER,
thank you for your answer. Still it is not clear about the ability of users to cancel their own reservation.:
10. Registered wordpress users shall be able to cancel their registration
Users have access to all the reservations.
What does it mean? Can the user cancel his reservation or not?
11. (Optional) Registered wordpress users shall be able to see all their registrations for all events, but not registrations of others. In another words, any user shall be able to login and see all bookings/registrations he has done.
No
What does it mean exactly? do users see registrations of everybody? Or do they see no registrations at all?
