When Alec draws both Walther P99's, the gun in his left hand has a "load indicator" red dot, while the right hand gun does not. This was due to the red dot being glued to the back of the gun, and fell off in the woods right before the filming.
When Alec leans over to the red valve and turns it, you can see the map fall out of the cameraman's pocket and into the creek. (Later in the bloopers, the cameraman is trying to fish the soaked map out of the creek with a long branch.)