It seems like CAD files for whatever reason don’t work well with the IR in Corona for C4D. Attached is a screenshot of a regular render and an IR preview. The difference is… noticeable
I tried welding the mesh together and I’ve also made sure that the phong angle is “ok”. The same mesh renders perfectly in 3ds Max.
Thanks for the images. This looks like the good old problem with normals in IR to me… We’ll need to have a look at it again, when we have finished programming of features for Beta 2.