Hi, does this also happen with other objects or only with this car? Does it happen with some standard geometry like teapot? I just checked and it doesn't happen for me. Which Corona version are you using? Were you using some other version before, especially A6, or did you change some files, for example the old "proxy exporter bugfix" that you put in scripts folder? I would try cleaning everything (use Corona uninstaller + manually search for Corona files in 3ds Max installation folder and in AppData and remove them), and installing newest version of Corona again.