Another way to do this is to merge the two actual projects by copying the
contents of one project into the clipboard and then pasting it over another.
To do this open the first project and click on the timeline/storyboard and
press Ctrl-A to select everything. Press Ctrl-C to copy everything selected
to clipboard. Now without doing any thing else open the other project and
change to timeline view. Place your timeline marker at the end or start
where you want to merge the first project's contents. Then press Ctrl-V.
Save as a different project name.