User Guide
Background
To use existing PDF as a background for your imposition, click background.
Choose the PDF.
If the PDF has more then one page, these are repeated as necessary (1-2-3-1-2-3). You can use the background option for Variable data printing. Put the variable data into one PDF, the rest into another and then use it as a background for the first one. Then make sure that "PDF optimization" is ON at your RIP (tested with CREO CXP6000) and it will RIP the pages very fast because it will recognise that the background repeats.