Cinerender rendering strange artifacts on AC objects with Rhino - Grasshopper adjacent objects

[keene kopper]

As you can see in the two screenshots (one on model view, and another a cinerender rendering), cinerender is rendering strange artifacts (in red dashed lines) on objects that are adjacent to rhino-grasshopper made closed polysurfaces. All walls in these views are AC. The window openings are made with *solid* morph solids, subtracting from the wall elements. The rhino element (a *solid* morph once in AC) is the vaulted ceiling, which was then subtracted from with the walls below (and still solid after the subtraction). This was done to prevent slight overlap between the morph and wall, and so create the lines of intersection in the model's views including elevations/sections, etc.

It does seem that even with the grasshopper/rhino objects off, the artifacts still happen in the rendering. So possibly its because of the solid subtractions' geometry? I've extended and trimmed the faces of the solid subtractors to the faces of the walls to be sure they are flush, but that has not helped. 

Ultimately, I'm not sure if its the rhino-grasshopper objects, or the solid subtractors' geometry. But either way, any help on the artifacts would be appreciated! 

See screenshots. 

Operating system used: Mac Apple Silicon 15.6.1