Made my second visit to Japan since obtaining TTP and I am now 4/4 on needing manual intervention from staff to get my passport read by the readers. It always eventually works, but never works the first time, and always requires multiple round trips between the support desk and the reader machine while the bewildered staff learn how TTP is supposed to work.
My passport is getting full and also old so maybe it will work better for me with a new passport. We'll see!