Bogdan, I am not trying to step in Christopher's shoes, and he will be able to clarify better than I can, however, the very words of Christopher are as follows, and I believe that they answer your question:
"Your print should be the VERY BEST print that you personally can make. I personally want to discourage prints that are not the personal work of the participant"
...and this is aside the fact, that I'd expect an optically printed output.
Yes that's what I read from his guidelines too, I just thought that prints from Kodachrome might be an exception.