Corona physical material’s preset warning is too sensitive and annoys users more often than it helps. I never use presets, but i get warnings about resetting some material properties all the time.
Steps to reproduce: (i know that it’s possible to trigger false positive warning without 3rd party plugins, but at the moment i can’t think of any of them, so i’m providing a way how to trigger it with RizomUV bridge script, which basically just exports selected object to an OBJ file and then imports it back) create a simple edit poly object, apply Corona physical material to it, do not select any presets!, using bridge script send the object to RizomUV, save it there, so the object would be sent back to Max, you immediately will be greeted by the Corona’s warning about physical material’s presets, even if you didn’t use any.