I did it once (civ 5). It took forever for them to answer and it ended up that they blamed Steam (i.e. they asked me to contact Steam support). Steam (I had a support ticket with them as well on the same issue) did the same thing, they blamed 2k (i.e. the asked me to contact 2k support). The whole thing ran into the sand, but it was fixed later on (months later when I tried again, it worked).
But I'm sure they do help some times. I'm sure of it. Almost sure of it. Someone ...
Perhaps I should mention that my problem was not ingame bugs, it was a download issue. Perhaps it is different with if is ingame bugs.