Word/Acrobat VBA automation problem

I'm using Adobe Acrobat 5 and Word 2002 and am writing some macros to output a document as a .pdf file. Web wisdom says I first need to convert the file to a PostScript one and then covert this to a pdf using Distiller.

Here's what I've got so far:

1. A reference to the Acrobat library at Project level

2. A class module ("Class1") as follows:

Public WithEvents oDIst As PDFDistiller

Private Sub Class_Initialize()

    Set oDIst = New PDFDistiller
   
End Sub

3. A macro in a regular module as follows:

Sub SaveAsWMA()
   
    Dim myPDFDist As Class1

    oldPrinter = ActivePrinter
    psFilename = "c:\watermarker output\wma\"& myname & ".ps"
    pdfFilename = "c:\watermarker output\wma\"& myname" & ".pdf"

    Application.ActivePrinter = "Acrobat Distiller"
   
    ActiveDocument.PrintOut Background:=False, printtofile:=True, outputfilename:=psFilename
   
    Set myPDFDist = New Class1
    Call myPDFDist.oDIst.FileToPDF(psfilname, pdffilemane, "")
   
    Application.ActivePrinter = oldPrinter
End Sub

This seems consistent with a few examples I've seen on the web. The problem is, this hangs Word when I run it. I get an hourglass and Word's title bar reports 'not responding'. This has happened on 2 different machines.

It looks like it actually hangs on the conversion to PostScript, because a .ps file is never created.

Where have I gone wrong?

Ray