it would be very useful to provide backup in a single file map, images and attachments.
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For now, when you move a map from one computer to another, all attachments are lost (unless you took the precaution to bring them together in a directory that carries with it, of course) .
To maintain compatibility with current version, one could use export/import menu with a new "heavy and full xml" option.
I agree, it would be great if a feature is added to include files / attachments within the map (like other products offer this feature).
+1 on this idea. It would be good to be able to share maps with others, and have attachments go with them.