This is a beautiful tune played by the wonderful Buzzby McMillan on Old Blind Dogs’ "Close to the Bone." That’s about all I know—I don’t know the composer but would be interested in learning. The second half of the ‘B’ part is really just a variation that Buzzby plays just before the fiddle jumps in.
The composer is W.G. McMillan(Buzzby himself),
"the inspiration coming from the hall of the same name at the
findhorn foundation near Forres,Banffshire"
Fred Morrison has written a reel in G about the very same hall and given it the very same name.