Images with CMYK in PDF Architect5

I have just purchased PDF Architect5, after trying PDF creator.
PFD Creator will convert Word Documents containing images which have CMYK colour profiles to PDF OK. However, if I insert an image with CMYK into the PDF with Architect, the image is converted to a rgb colour profile. I have to have CMYK for printing purposes. How can I configure PDF Architect to accept CMYK?