Again, could be co-incidental. The addition of phone GPS would prove this one way or another.
I don't think it's highly unlikely at all. There are always people out and about at strange times of the night for whatever reason. I'm from a small Scottish community and i have seen this in most villages that i've stayed in. And again, it 'looked' like they were carrying someone but the CCTV isn't clear enough to prove or disprove this.
You would, but that doesn't mean to say that some people might not come forward to explain themselves for whatever reason. A lot of people might not purely because they don't want to implicate themselves in a murder.
I know a lot of people want to bend certain aspects of this case to fit, but the harsh truth is that a lot of the details cannot be proven, or at least can be explained. Again, i'm not saying that the accused isn't necessarily guilty, i'm just not being naive in trying to make the scene fit the crime.