http://www.mizahar.com/lore/Flux reference
From the looks of it, initiation is similar only in the aspect of Djed invasion from the teacher. Odds are it's going to feel pretty intense and uncomfortable, you have someone disrupting with your life force after all. My guess is the initiation focuses more on the Djed being inserted at some tips in the body, more likely the heavy neural areas where sensations are at their greatest, like the finger tips. From there your teacher will spread throughout the entire body in a method similar to how the flux will work later on, opening the pathways for the Djed flow, if you will. From there they pull out, you feel disgusted, and it goes from there to learning control of the flux. I didn't notice an inititation detail, but I can garantee it's not going to be peaceful, calm, or comfortable. Obviously it can be lessened to a degree depending on how well versed the teacher is.
Hope this helped, stop by in chat for more questions. Check with the wiki and mods before you follow the above, that's just my logical assumption.
