Hello,
I changed all local settings, and nothing changed.
the last thing I did : reinstall my windows 10 machines ... which took a while...
I can confirm now it is working as expected. RA and DEC got the values. this is still frustating to know there's some situation where it does not work and can happen again in the future 
thanks all for your time and help. (anyway, I bought the software after this success 
)