I have no expertise here at all and am depending solely on ספר אוצר המחשבה published anonymously in 1981, with a haskama from הרב יצחק יעקב ווייס and a note about the specifics signed by a “ד ורנר”. It was published by מאורות דעת in Israel.
The Sefer draws upon all of Reb Tzakok’s seforim. It includes a short biography and analysis of his thought, it offers comments by him according to topic, and is broken down into 14 chapters with a couple of hundred entries in all.
I’ll be presenting synopses of Reb Tzadok’s remarks, offer remarks of my own when that’s called for, then cite the work it’s taken from.
Rabbi Yaakov Feldman