You may not be aware of it, but a translation of the Institutes of the First Monks into English has recently become available. It is published in Rome as a hard-cover work by the Edizione Carmelitiana and costs in the neighborhood of $20.00.
The importance of this work is that it was for a long time second only to the Rule of St. Albert as a source book for understanding the Carmelite charism, way, and path. It was enormously important in the reformation of the order brought about by St. Teresa of Avila and St. John of the Cross, being the main source of inspiration for the "return to contemplation."
I don't know whether or not it could be considered as important a source today, but then, until one reads it, that question must remain unresolved.
Stephen, thank you for the heads up in regards to the translation of the "Institutes of the First Monks".