Severe graphic glitches on macbook air 2012

I bought that game because some reviewers wrote that they are running it perfectly on a 2011 macbook air with native resolution.
On my new Macbook Air 2012 (i5, 8 GB RAM, 256 GB SSD) its defintely NOT running well!

In the native resolution with ALL the settings switched to MINIMUM or OFF, I get a framerate that is barely playable (around 20, but can drop to 10 and lower).

Then there is a major issue with the loading of textures being delayed (and popping into sight) which is pretty annoying.

But the worst issue is that there is a glitch which causes some textures to appear as blue tiles before they are loaded.
(they disappear when you dont move, but when moving or turning you constantly have blue tiles jumping at you…)

And those graphical glitches together with the low framerate make the game no pleasure to play at all!

I have the suspicion that those reviews telling that it runs great on a macbook air were fake!

Dont buy!!!

Benjamin227 about RAGE®: Campaign Edition