Hi, Yonten and Pema-
The Milarepa sadhana available at KDK is the one written by Kongtrul, and the one that is practiced in 3 year retreat. It can also be practiced as a principal practice, or as a "special occasion" puja with Tsok. We've done it at KDK a few times.
It is a "LaDrup," or a "Sadhana of the Lama," and I would classify it as Highest Yoga Tantra. However, it's my understanding that it can be "done" in a group setting, on special occasions for example, even without the specific empowerment--in other words, at KDK I don't believe there are restrictions on viewing, or even purchasing, the texts, but I could be wrong--I haven't looked at the bookstore section of a Newsletter in quite some time.
It does involve self-generation as Vajrayogini, with a bit more "detail" than one would find in a standard "ngondro."
I would say it's best to get the empowerment, of course, and the detailed instructions on practice, prior to attempting to practice this sadhana. But it can be engaged in as a supplication, and tsok, and that's the way we do it when practicing in semi-public group occasions.
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