We are experiencing same issue and we would like to know if it fixing any future road map(if it consider bug).or else if this requirement consider as a feature then do I need to raise daycare ticket? Is there any common resolution?

Multi-field example implementation shows belo URL and let us know if you find any specific issues:Experiencing Adobe Experience Manager - Day CQ: AEM 64 - Touch UI Nested Composite Multifield Using Coral 3

Can JCR encrypt and store files similar to encryption options in other databases?