I had been getting type 2 errors prior to updating to 1.1, mostly involving the shader browser, when trying to save new or modified shaders. Carrara is more stable now. I guess you would get errors from the ATI extension when you try to render or maybe try to move things in the assembly screen.. I have the ATI 128 accelerator so I'll have to leave the ATI 128 extension active. I don't get errors in the assembly or render screens (knock on wood ;-) What other Mac OS errors in Carrara have you seen? Possibly regarding the misinterpretation of Poser mtl files? sincerely, Miss Nancy