RSPPFPROCESS PDFs into one file

I have created ERS action files via a modified Version of BBPERS which allows me to recreate the credit items of the past time.

Now I want to create the PDFs with the program RSPPFPROCESS. It works fine but the Problem is it creates one spool per invoice.

How can I get all created PDF files into one spool? I can't attach them to one another because they are immediately printed when the program has run. This is another Problem: How can I make it not print directly?

Thanks in advance!