I too experienced your dilemma. However, if you installed PM7 and Acrobat Distiller 6 but cannot export to PDF because no suitable Postscript Driver is found, then install MS Publisher Imagesetter found in Vista's Printer setup. Go to Printers -> Add Printer -> Add a Local Printer -> Dialogue Box

left pane Manufacturer) choose Generic, (right pane Printers) choose MS Publisher Imagesetter.
I installed this printer on LP1 port.
Go to PM7
Open a document
File menu: Document Setup -> Compose to Printer (choose MS Publisher Imagesetter)
File menu: Export-> Adobe PDF
(PDF Options now appear)
Export
Result: PDF document.
The experts here will attest or argue. But this worked for me. Good luck.
-mtb