Apart from instruction on how to do zazen, there is no instruction in Zen. True Zen masters never claim to be masters and rarely teach. They ask their students to question themselves. They give questions in the form of koans. The presence of a master saying nothing, often has profound effect.
There is no right way or wrong way, for how can there be when it is one's intent to walk through a gateless gate, going nowhere.
My journey is unique, as is everyone else's. Currently I am working through my own karma, that is truly ancient and huge. Listening to another Zen practitioner sharing his/her experience can be inspiring and trigger insights in myself, but it is still my journey, and whilst listening to the other practitioner, their shared experience becomes my unique experience - so listening without judgment and with total focus is valuable, whether or not I realize it.
Past life karma? How can it be when the past is an illusion? Intelligent cellular memory? Maybe, maybe not. This is all irrelevant anyway when all there is, is now.
If you wish... Please share you experiences...