I have been at it for a couple of days with no real progress.
the only thing I have yet to try is the esptool, which I think I will in the next few hours.
kind of a last thing to try.
What i have used so far is the xtcom tool and the multi (batch bin) upload tool. (even combined the firmware)
At firmware (compiled)
IoT demo firmware (compiled)
Simplistic custom firmware (compiled)
all failed to boot correctly.