At first I want to say no one is your legal advisors here. So you shouldn't depend on all of reply here. But yes, you might get few ideas from here which would be helpful for your next step.
I strongly believe you need hire a lawyer from your country where you are going to run your business. So you will get which documents you need for operate your business legally from your country. If you are accepting only crypto-currency then I don't think you need any other documents except script license. I am not aware if there is any international rules for gambling website.
Just pm a few casino admins here in the forum. There will be there for sure who will answer you. Better then create a topic about it and get a lot of nonsense help ;-)
Personally I don't believe that someone from admin will share full details. Because that is business, they have their own policies. So I don't think someone will expose it.