Hey, I was having trouble with the s2 mini until I put a 1k pulldown resistor on the boot button. Not sure why that was missing from the layout, but it’s a simple fix.
What I did was cut the trace from the 0 button (that goes to the ESP), scrape off the solder mask, then solder the resistor to the via that goes off to the ESP.
It’s small, but if you get a good magnifier and a sharp x-acto, it’s doable.