I'm trying to log in to Game Center using my Apple ID but it just won't let me do it. Actually, nothing happens: no error messages, just nothing.
I think there is an issue, because I also get a pop-up window where I suppose a new registration could be done within the same program, but it's blank (Annulla means Cancel):
Apart from what is being suggested in this question about Chess over Game Center, why isn't the simple log in working? I could use the workaround but I want the standard way to work anyways.