Is anyone here familiar with the practice of Thrinley Nyingpo or done the Sadhana Ritual Course in Boudha before ? Thanks.
I am somewhat familiar with the practice.
I was staying at Nagi Gompa last year while the ritual course was in progress. I didn't really participate except for a couple of days for the tsog at the very end of it. I believe the participants first had 2 weeks of theory down in Boudhanath, and then 2 weeks up at Nagi where they were instructed in playing the instruments for group and individual practice ("bell puja" and "drum puja"), leading the chants, being chöpön as well as using bell, dorje, damaru etc. They also learned how to make the tormas.
As Magnus says, the root text can perhaps be speeded through in 15 minutes - but that is not how it is taught at the ritual course. There you learn how to do all the lineage chants, extra prayers etc according to the tradition with melodies and all. I rarely speed through that in less than an hour. So the length can be adjusted according to how much time you have.
The teacher was Phakchok Rinpoche's attendant, and British Ani Laura translated. The both did a great job, and the course is very thorough. Unless you have some familiarity with the practice, or sadhana practice in general, it's tough going and a lot to digest - both in terms of theory, but also learning to use the instruments, mudras, tormas, chöpön work etc. Whether you like that or not is an individual matter. I love it! And I love the practice.