I've not looked at Graham's code in awhile, but we worked on this together. I'm pretty sure that you will need to change your Sub to a Function in this format:
Code:
Function FontChangeArial16Blue(ByRef oDoc As Word.Document) As Boolean
On Error GoTo Err_Handler
With oDoc.Range.Font
.Size = 16
.Name = "Arial Unicode MS"
.Color = wdColorBlue
End With
FontChangeArial16Blue = True
lbl_Exit:
Exit Function
Err_Handler:
FontChangeArial16Blue = False
Resume lbl_Exit
End Function