Hey @ssw! 
So let me explain a bit the differences between Rhino and GH in terms of applicationIDs, as there are some limitations on the GH side
- Grasshopper has no notion of “applicationIDs or GUIDs” as there is no persistence for objects (everything gets executed again on every run), so we can’t keep track of what Grasshopper was a Rhino object before (at least… not automatically)
- When we convert an object
ToNative, we’ll loose that application ID as Grasshopper doesn’t have support for object metadata
I’m not really sure how your interaction between Grasshopper and Rhino is happening. So let me just ask for some clarification.
- You are creating some massing geometry (I guess BREPS) in Rhino
- You are sending this to Speckle
- You are receiving that sent data in Grasshopper
- Some operations are made in Grasshopper
-
Here’s where I’m not sure about the details
Since you said you’re not sending, I’m assuming you use Grasshopper to bake geometry onto the Rhino file? How is the interaction between GH and Rhino happening?
If you’re using GH to bake, that bake operation will most definitely create new GUIDS for each baked object (even if you use Elefront, you’ll face the same issue on the first bake)
If instead you are sending from Grasshopper to Speckle to Rhino, you can have total control over the applicationIDs of the objects sent from Grasshopper, and if these are found when receiving in Rhino, they will be properly updated/replaced.
There’s several threads about this, you can find a usefull reply by Matteo here Add a Revit phase-parameter with ExtendSpeckleObject in GH - #6 by teocomi