How can I copy designs between 2 projects?

I have tried in “My dashboard” view, click on the “copy project” icon in the project I would like to copy.

An error message pop up:
“No such file or directory – /home/floorplanner/beta/release/20091113180210/public/designs/18133319/18171446.xml”

After that, it has created an empty new project, but don’t copy the designs.