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I haven't used it for a year or so, but I think you could export the database design to DXL (See "Exporting and Importing DXL" in the Help File). It's a bit fiddly, but I think you'll be able to find/replace the filepaths in the output file and import it back in.
I'll have a bit more of a think over the weekend and maybe write some test code.
EDIT: I've just seen the date on your question - I hope you found a non-manual way of doing it!
Feedback response number WEBBAUXN4E created by Phil M Jones on 01/12/2018