yea, problems. rtw is unplayable with alot of bugs. that rubber physics just make new angle collision, PhysX its Nvidia physics engine and why you think px have dx11
what are the benefits of directx 11 for wa? directx 9 is enough, also it would be gg win xp (happy impo, angry wormers). it's not rly needed, and wa 4.0 will pwn anyway