Runs perfectly on mbpr, but requires additional app to enable gpu switching
Runs perfectly, no lag on high settings with gfx card switcher. The problem I found was that my mbp was not switching to discrete graphics on its own. I downloaded gfx switcher, (google it, gfx.io) and used that (note, I dot not own or have any connection with the software or its maker) to switch the graphics card to discrete manually.
Great Game.
Net_Dragon about
The Witcher 2