The problem with PDF chart paper size goes back to a change that Microsoft made in Vista and Win7 - and I assume still in Win8. Google for 'Win7 Printer Button Page Setup' to see the problems caused in many many programs. A Microsoft developer described the code change like this:
"Unfortunately, our developers did remove the “Printer…” button on PageSetupDlg for Windows Vista. This was done for specific reason. It is because they do not recommend switching printers from the page setup dialog, where there is some information in the page setup dialog which is printer specific."
The workaround is to make your PDF printer the default printer and also set the paper size in the printer properties _before opening FTM_ and making your chart. You can make the chart first so you know the size and then save the chart to come back to. I've used this technique in FTM, RM6 and VCF/TMG. There is a big discussion on the Visual Chartform forum; see the pinned message at the top 'Print Large Charts to PDF'.