Is anyone having any problems with these missions? Mission 1 won't let me use the grappling hook consistently. I completed the mission once but haven't been able to use the hook since - it stays grayed out. Mission 3 - I can't get my ships past the gates. Of course I can get the sub past, but it won't bombard the gatehouse. [Edited on 09.11.2011 8:22 AM PDT]