yes i added TCascadeType.Flush to the Many-Valued Association.
...
fAssociation := aMappingExplorer.GetAssociationByPropertyName(TInvoice, 'InvoiceItemsList');
if fAssociation <> nil then
fAssociation.Cascade := fAssociation.Cascade + [TCascadeType.Flush];
...
Typical case Saving a Invoice(Master) and InvoiceItems(Detail).
More, cascadeFlush simple does not save InvoiceItems when Save Invoice Object with single Object and CascadeFlush , but should?
thanks