Downloaded this in order to compile a bunch of related docs into one pdf file, but I can't figure out how. Once I "print" one doc, it does not let me add something else to the file, only replace it. What am I doing wrong?
You cannot merge PDFs with doPDF, so if you want to have content from different documents into a single PDF you have to try combining them in a single document before doing the conversion. We have another product (commercial) that supports this feature, you can see http://www.novapdf.com/kb/merge-pdf-files-with-novapdf-146.html