Some properties are missing the indexer to access an item. Especially BuiltInDocumentProperties and CustomDocumentProperties on Word.Document should have it.
For BuiltInDocumentProperties it should be possible to access an item using the WdBuiltInProperty enum (BuiltInDocumentProperties[WdBuiltInProperty.wdPropertyAuthor])
For BuiltInDocumentProperties it should be possible to access an item using the WdBuiltInProperty enum (BuiltInDocumentProperties[WdBuiltInProperty.wdPropertyAuthor])
