You can use getURL to open the PDF file if you like, even if the projector is going to run from a CD. The PDF file will open in a browser IF the user has the Acrobat Reader plugin installed for their browser.

I have a few clues about how SWF Studio works if you want to give that a shot.

With SWF Studio, or if you just want to use something other than getURL to open the PDF, what you have to do is find the code behind the button (easy if you wrote it, less fun if someone else wrote it) that reads the PDF file name from the XML and modify that code to do what you want.