I've downloaded the latest OTMonitor and connected it through TCP port.
It started and went to like 6% (not sure) then stop. Probably my WiFi connection had an hiccup exactly then!

I've tried again but OTMonitor briefly said "Switching to self-programming mode" followed by "Please manually reset the OpenTherm Gateway"
I've then plugged out and replugged power supply and repeated the process, with no luck.
So I've detached the OTGW, removed the NodeMCU and attached it directly to my USB to TTL, (GND,RX-TX) after selecting the right COM port in OTMonitor, but no luck.

I've also followed and replicated what's already happened at this blog post that seem absolutely identical to what's happened to me, and I've also tried to swap RX/TX cable but nothing ever seems to change.
What's worst is that I can't see any response from the OTGW on the log (attached).
Is there something I can do ? Buy a compatible PIC Programmer maybe ?

Thanks,
Marco