Squats look pretty good, lean over a little bit more for better hip drive. But PLEASE do not walk backwards into the rack. You are going to have a bad wreck like that because you can't see where you're going with a heavy bar.
About the deadlift, two comments: 1.) I'll bet your first rep felt better that the last 4, because you started with a good back angle but ended up too vertical for the last 4, with your shoulders behind the bar. This is because 2.) you set the first rep down by bending your knees first instead of shoving your ass back and getting your knees out of the way. This makes your back too vertical and causes the bar to go forward out around your knees. This is dealt with on pages 127-29 of BBT.