Oh is it that hard of a question? Anyone can launch the game on his/her pc and confirm the shadow related question. And so many people play multi and co-op and none can answer about that too?
Or if its due to the lack of system configuration, here it is-
C2D e7400 @ 3.2GHz
3gb ddr2 ram
asus 560ti gtx ( 267.XX driver)
19" LCD @ 1366x768 ( i know its small but i've become used to it)
Gigabyte G31M ES2L rev 1.1