Autocad disables late 2012 iMac

I´ve been looking for someone with the same problem, but I couldn´t.

When I install autocad, it make happens strange things with the screen specially when I move between differents desktops, it appears like waves in the borders of the moving desktops. It also happens when I change the size of the autocad windows.
I put two videos where you can see the problem.
I took the iMac to the apple store, thinking that could be a hardware problem, but after changing every piece and many restores, the problem appears again when I install autocad.
I tried to report it, sending mails, but the support team just says me to do it here, so here I am, waiting for someone to listen me and update the program.

Thanks

Link to my video in youtube with the problem: http://youtu.be/vM_DXHMCWmQ