Rikk, I don't ever recall the sort order changing when returning from Photoshop but I have had the sort order change several time because of moving the photos slightly in the filmstrip. This happens accidentally and more often when I select photos and start to move them to a collection and change my mind and want to select different photos. I start the drag, drag back to their original location, let go of the mouse and the sort changes. As John said, the sort shouldn't change unless you actually move the photos in the filmstrip.
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