AqQA 1.5 has a known issue with printing diagrams (Piper plots, etc.) to PDF using Adobe Acrobat. Possible work-arounds include:
Choose File | Save Image As and save the diagram as a graphic file. Insert that file into a Word (or similar) document and print to PDF from there.
Use a different PDF printer. Our tests show that PDFCreator, a free program which we use at RockWare with some frequency, prints fine.
Molly Mayfield
RockWare Inc