The Keller rope tie that Tony uses doesn't work when the person binding him directly ties both of his hands together at the same time.
After the bullet grazes Tony's head, there's a fair amount of blood on his forehead when he wakes up. But it all disappears in the next shot when he leaves the ice factory, and no indication that he wiped it off on hand or clothes.
Jerry tells Tony that he's going to get a C4 for a chopper. The model he ends up getting is not a C4, but rather a standard two-blade civilian helicopter.