Hello Andrea,
You can contact MDA by its current main email address: support [at] hauptwerk.com. Please send an email to that address to be assigned any ID codes that you need. Francois normally handles that email address and he's very prompt and helpful and there's no charge for being allocated IDs. (He's in Canada, so there might be a delay of a few hours, due to the difference in time-zone.) N.B. Please under no circumstances release a sample set publicly that uses codes that you haven't been assigned since it may well break other producers' existing or future sample sets for users. Many thanks.