Dear "nomorealive",
I had the same problem, my controller worked but not my keyboard and mouse. About the same error displays when i try to launch the game. I also tried to solve the problem by setting manually nvidia as graphic card, but the same problem was still there. (I knew the trick because i already did it for pvz gw1)
BUT i found a TEMPORARY solution to be able to play with my keyboard and mouse. First of all i plug in my controller and my keyboard and mouse. When the intel error displays, i accept it. Then i pass the beginning scenes, with "A" on my xbox 360 controller. When comes the moment that i am suppose to be able to move, i can only with my controller, with it i go to settings and put my game on WINDOW MODE. After that i can play with my keyboard and mouse
I hope that my temporary solution will work for you too. And I hope that the problem will be solved definitively soon.
(i am sorry for my bad english, i hope you can undestand me, if not i could also write it in frensh or dutch if necessary)
mosselini1