Hi Ryan -
As far as I can keep up with,
Rhino Inside is open-source. It’s just a developer toolkit of some sort to allow you to create a plug-in that will let you run Rhino inside of a different program. For most of these other programs, you are on your own to create a plug-in (or plug-ins are being developed by 3rd party developers. We are actively working on a plug-in that allows you to run Rhino inside of Revit. That plug-in is free (and also open-source if I’m not mistaken). But you will need to have a valid Rhino license to run this. This only works with Rhino 7 and when Rhino 7 ships, you will need a Rhino 7 license.
Rhino.Compute allows you to run computations on Rhino that is running on a machine running Windows Server OS. This is where Core-Hour Billing comes into play. More information on that is here: