Having recently dived into this book I thought it would be a great Grimoire to discuss as there is just so much good stuff in it to work with. Personally I have decided to dedicate myself to invoking each spirit in the book through out this year. I have already invoked a number from many spheres but I am going through from the beginning and doing them one by one right now. I have found that by doing this work, I have greatly increased the harmony I feel in life after my awakening. The past few years having been leading up to being ready to work through this book, despite me not having completed IIH all the way to level 8 (as my initiation started at 10 and is working its way around). I am very clearly connecting with each spirit so far and the range of experiences is quite interesting as I am still developing/healing my clairvoyance (flashes but very tiring to hold still after years instead of just naturally always there like eyesight) but my clairsentience is very well developed. Having worked through some spheres, I already have some spirits I really love working with (I really love Malchjdael and Cargoste, he is hilarious with existential Allish humor and she just has a feel about her I enjoy). As of last night I just wrapped up the spirits of the element fire and I'm moving on to the next. I've found that by sitting in my temple, I can flow through the 3 bodies and call each one in rather easily now that I've harmonized with the Grimoire.
For those of you working through this book, I'd love to hear what your experiences have been like. Considering the depth of the work, I'm surprised I haven't seen more of a discussion around here on it in the first place.