Mike: Yes, I did a shortcut, but as I said in my previous post, the launcher's Play option has worked lately, I just have to close the Access violation message window and the game runs.
Now I've had a look in the nwn2 boards and what I've found out -- besides the fact that I have an account with my old rpgdot username over there, I had completely forgotten -- is that I'm not alone with this problem. If I've understood correctly (and I probably didn't), the problem may be related to the newest nvidia driver in which a profile for the game has been set up but with only the nwn2.exe file binded to it, not all of them (or just the Main). There is a workaround to edit the profile using something called Nhancer but for now I'll wait and see if the next patch or a new driver won't fix the problem.