Someone else without the same problem, but can figure it out what can I try to do?
I don't have the same system, nor problem - but I did have a similar behavior with an HTPC I built some time ago. The problem was with the signal pulse length from the remote - essentially it kept sending the 'on' IR sequence long enough to be interpreted as a second 'off' (either that or as holding the power button on for 4 secs - which was the forced shutdown for the board).
Unfortunately, the only solution I found was to use a different remote control which was compatible (as far as codes were concerned). I have no idea if this is your problem however. One thing you could try is push the power on button on the remote, and then immediately cover the IR diode (or the receiver on the NUC if that's easier). If it stays on, the signal duration is the problem... if not, it's a different problem - likely in the implementation.
I didn't see force-shutdown settings in the EFI documentation for that NUC, but I do see settings for CIR power-on (which I assume you have enabled for the remote to work). If you don't need them you could try disabling all other wake-on events
including the "Power On by USB KB/Remote" settings - that's in "Advanced>ACPI" settings. Try the opposite as well if that doesn't work (i.e. USB KB/Remote
enabled and CIR Power on
disabled). I would hope that isn't the case, but it's possible that the CIR is an enumerated USB device in EFI and if both are enabled, they are conflicting.