I'm using the Valby translation which has the commentary and the original root tantra. The Valby translation is in my opinion superb and so far three volumes have been published covering chapters 1-40 and their commentary. The whole tantra is also available as translated by Adriano Clemente.
As a student with 25 years background of practice I have never come across such an amazing text. It's superb. For those who wish to fully understand the view of Dzogchen Semde then I cannot recommend this text highly enough. It is especially important text for those who come from a Madhyamaka background and who (like me) mistook some of the finer points of Dzogchen Semde. My assertion would be that it is impossible to practice Thögyal without first realizing the meaning of the Dzogchen view as outlined in Kunjed Gyalpo. This is just my assertion though and for some it may not be necessary.
The Blessed One said:
"What is the All? Simply the eye & forms, ear & sounds, nose & aromas, tongue & flavors, body & tactile sensations, intellect & ideas. This, monks, is called the All. Anyone who would say, 'Repudiating this All, I will describe another,' if questioned on what exactly might be the grounds for his statement, would be unable to explain, and furthermore, would be put to grief. Why? Because it lies beyond range." Sabba Sutta.