> Unfortunately, the one I need most, pdf version, is not included.

Russell,

The PDF file is simply a text file. If you open one up using Notepad or any other text editor, you will find the first line to show the following:
%PDF-x.x

Where the x.x is the version number of the PDF document.

So, you can read the first line of the PDF document using low-level file I/O to obtain it using VFP.