I was just doing some testing. Working on some ideas for expanded gamut printing.
First, I was reviewing my color server, which doesn't "see" the n-channel (or multi-channel) profiles. Then I looked at InDesign to see if I could either create a document in a n-channel color space or convert to an n-channel color space during export to PDF. Then I created a Hexachrome file in Photoshop and tried to import it into InDesign - I also tried to place it into Illustrator. Neither program will accept the file.
Lastly, I tried to edit a PDF. I tried using the Touch-Up Object tool to edit an image, but found that I couldn't save the resulting edited image back into the PDF. I also tried to place the Hex image on a layer, but that, too, failed.