Calexo, thanks. Renaming embedded photos worked on both Mac Mavericks and Win 8.1 Evernote versions. After renaming the images "filename.jpeg" to "filename.jpg" in Evernote, I was able to open the images with external photo editors, applying changes using the external editor, and then after saving the file in the external editor, the updates were reflected in the Evernote note. It was very frustrating to first find this synch-to-external-editor problem AFTER making a bunch of updates in the photo editor. I use Evernote mostly to annotate photos I take with my android smartphone. The inability to efficiently modify those images while staying in the context of the Evernote note means Evernote isn't functional for me.