Hi Dan C,
Thank you very much for your answer.
Finally, I figured it out. I extracted my own ICC profile from a CMYK picture, then I opened the package contents of the 3 apps (Publisher, Design and Photo) and I copied my ICC profile in it. Now, my own CMYK profile appears in the "preferences/colors CMYK" menu of the 3 apps. I can work with the space color that I always used with Photoshop.
In fact, it would be nice if we (Affinity apps users) could import our .csf files from Photoshop.
Another thing, it would be helpful if we could open .indd files with Publisher and .ai files with Designer.
Best regards.