I've recently been following along on this video series on the Gomchen Lam Rim and would very much like to find a copy of the root text so I can follow along better and read ahead, but I can't seem to find it anywhere. I would especially like to find a free pdf somewhere, but I'm also okay with proprietary books.
I have just been trying to locate the text also. This link mentions,
The Pearl Garland: An Anthology of Lamrims
translated from the Tibetan under Venerable Dagpo Rinpoche’s guidance by Rosemary Patton, Editions Guepele (France), 2012.