In the Navigator, activate the Organizer Palette. There, click the "Project Chooser" button in the upper left, and use the "Browse Project". Using this you can select a file and open its Project Browser structure.
Display the Layout of that Project on the left pane, and the layout of your current Project in the right pane.
Then you can copy Layouts and Master Layouts from the other project to your current project using drag-and-drop.
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