1. Open the both projects and set Wiev to "Thumnails" for both;
2. Split the window (Window --> Split) for wieving the both projects.
3. Select the pages to be moved in the first project (using Shift/Option or Ctrl/Command)
4. Drag the selected pages from one project to the other; if you have problems, drag the pages to the front of the fist page in the destination project, then move them to the desired position.
I've tried these on QXP 8.1.6 on Windows.
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