As Winston Churchill once said...

"................. It is a riddle, wrapped in a mystery, inside an enigma; but perhaps there is a key........" That key is called Picasa©.

I doubt I shall ever discover either how, or why a day or two's photos vanished, apparently without trace, over the duration of a meal in another room.
I happen to have a copy of Picasa© on board and I had noticed that all photos were snatched up William Nilliam by said piece of software; but it never occurred to me that, having disappeared from where I had so carefully put them they would sneak off to cuddle in a corner with Picasa. It was only when I visited Picasa for some other reason that, mysteriously - there they were. Un edited, unadulterated, un-thrown out. I had tried to get photos of "The Lion & Lamb" & the Man playing the Organ, as we traversed Dunmail Raise.
NOT a howling success, got the Lion but not the Organist.
Must try later.