Thanks everyone for the help,
It's something to do with the premium serials, they do not activate the LightScribe function. Only ultra do, but then no LabelFlash support!!!
Since the version I bought wasn't the latest one I did download the latest version. Guess what happened when I install only the update (working as demo)? LightScribe was working, then I tried to enter my premium serial and both functions were working (LS and LF) but one only as Demo (it will expire soon LOL)
PS: Still waiting for Nero support, regarding this issue.