You cannot activate the club in more than one country. Your membership should always be active in the country website you shop from.
Points are only available in the country the orders were made to and cannot be transferred to another country account.
If you want to change where you are registered for the Club you need to deactivate your Club account in the country it is registered in, and sign up again in the new country website. Make sure only to deactivate your Club account not your "MyBoozt" account.