Thanks Howard, you are quite right, NE not NW although the location is right, just across the footbridge. You are also right that I confused Office Lock with River Lock but whilst there are electric hook up points there I don’t think they work. At least they didn’t when we were there.
I’m pretty sure the moorings in Granary Wharf are free, as they are in Royal Armouries. I know the gated section you mean but personally, despite the gate I don’t think I would feel safe on that mooring but that might just be me! Agree about the swing bridges which I imagine are particularly difficult for single handers.