Here is the way to get Blocks to Families using Rhino 8 components.
Generally the Block instances and the block definition are both used.
All the geometry of the block definition is extracted and placed in a Component Family. The block definition is always located at the 0,0,0 Origin. In this case the layer names are cub categories in Revit.
Then the Instances are found and used for the insertion location of the Family/Type in Revit.
This is a lot of new stuff, so I expect there will probably be questions.