Thank you Dina for your advice.
If I may, the question here is not related to software I think but rather to preparing a database which follows certain requirements, and there I cannot say more than what I already explained. And the request to provide an easy to understand manual which allows you to create a database that has been developed by someone with quite some effort, and is offered for a price, is maybe a bit demanding. I hope you understand.
Best wishes,
Andreas