Hi Pinklet,

You're running a Mac, right? I'm not having any issues here on this Mac Platform. 

Usually issues like that can be object/shader specific and can be fixed. Sometimes it's as easy as rebuilding the shader itself. If you're cranking up the photon settings, sometimes in combination with other shader settings, they fight each other.

If the objects causing the issues, open it in the vertex modeler and make sure that it doesn't have bad topology/mesh closures. 

As always, maker sure that you're also running the latest version of Carrara - 6.2

Mark