My French is very limited, so, unfortunately, I will have to answer you in English :-( You thread your warp through your heddles using the threading chart that Jane uses at the top of page 2. Where things are a bit different is when you sley your reed. Use the chart at the bottom centre of page 2 - in the centre of the warp on the loom, you are sleying the reed with 2 threads per dent, until you get to your silk threads. When you get to them, you sley 2 cotton threads and 1 silk thread per dent. Hope this makes sense!

I am just reading the pattern right now and the first 30 threads should be threaded on 1,2. They would go into 15 dents of the reed. Then you will have 2 bambu threads and 1 merino that would go inot the next dent and that would be repeated for 5 dents and you would then repeat that entire section 5 times. Your bambu's will always be on 1 and 2 and the Merinos will alternate on 3 and 4. Does this help?

Ah....the first one....the diagram is a partial representative of what is going on.....you have a bunch of 2 per dent and then you come to a 2 supps. You take the first one and put in in the group to the right and you take the 2nd supp and put it in with left pair. You will always have a 1and2 in a dent and sometimes there will be a supp with them side by side.
I think I go over that really well in the video. I can see how you misunderstood because you were counting the dents and there really should be another one in there. I'm so sorry, no one has ever asked that before.
Your fix will work perfectly. I will adjust that reed image in the next pattern run. Have you watched the video yet?

You got it.....then nothing is crossed over and it is simple and straight forward :)

I used 2 ends just to get a thicker supp and it seemed like the logical way to disperse them in the reed :)