Hi Moratorian,
I tried to view some of your shorebird fotos but seems that they may have been taken down. Anyway, I was re-directed to a site that may have the pictures in question. Suffice to say that the 3rd picture showing three birds is indeed of (clockwise from top left) a Sanderling, a Least Sandpiper, and a Baird's Sandpiper. Excellent picture! The Baird's shows the primary projection really well. If I'm looking at the wrong foto then I apologise for perhaps IDing birds that you had already ID'd.
All the best