No problem at all, thank you for your input!
What I can recall now from that experience is that I was using some basic template I used to avoid configuring some stuff once and again, so maybe the watchdog enable code was there, or was part of the debugging session code inserted.
So, taking out the mention on any "'watchdog entity" 
my issue was:
_ Two display objects were instantiated and started
_ The displays had timers to keep them refreshed as they were 74HC595 dynamic driven.
_ Each time the display was refreshed the timer was reseted for the next refresh.
_ The timer start time variable was wrongly declared as static, so one display reseted the timer for both displays.
_ The ESP32 rebooted every 5 seconds...
I believe that better describes my issues and my solution. And the library development thankfully arrived to an usable stage! Thank you once again @silentobserver .
Cheers!
Gaby.//