ImagingSound

I'm on PS3 and I have the same issue. I'm on the 3rd floor of clyde's castle I killed the Nazi's and need to brake the leg of the wooden platform then Nagasaki the platform and the latter comes down to get on the roof.... There is a tyre swing I'm supposed to be able to shoot but I can't , because the cross hair doesn't register the target. I can't brake the leg of the platform. I have tried different angles, and the different friends and different weapons, also I have left the castle and came back, died and went to a different save before that part and played it again and it did the same thing. I'm also meant to hit the leg of a table to make it collapse, but my attacks and farts are doing nothing. I have erased the game data on the computer, as well as got a new disc from gamestop and there was no change.