Need to get a document thumbnail

G'dday!!

I'm a programmer in XBase++ and I'm stucked with this issue: I need to get the graphic thumbnail of any document I load the program, such in my code (the real part):

     oAcrobat := XbpActiveXControl():new( oBitmapRef )

     oAcrobat:CLSID  := "{CA8A9780-280D-11CF-A24D-444553540000}"

     oAcrobat:create(,, {4,4}, {230,270} )

     oAcrobat:LoadFile( cNomArc )

     oBitmapRef:setData( oAcrobat:ExtractImage() )

     oBitmapRef:draw()

     oAcrobat:Destroy()

In bolded red, the method I thought to be the one to get me the thumbnail, BUT as you can guess, isn't working as I need. Wich would be the method to get ONE image of the document as a thumbnail to show to the user? Is there any other (easy) way to get it?

Thanks in advance...