In the past we have seen odd graphical behavior with the Retina screens and Revit. As the Retina displays were released after Revit 2013, it was not designed to work at such a high resolution. We have also seen these issues if the Project Browser or Properties Palette undocked from the main Revit window. Usually lowering the resolution fixes these types of issues.
Chris Aquino Technical Support Specialist Customer Service & Support Autodesk, Inc.