This is preposterous. Luca this is fooling nobody. Quit dodging the central point. DDR is not infringing your copyright, they forked from YOUR liberal license. Much as you'd like to put the genie back in the bottle you can't. The reality is that without OpenSource your project would not have experienced the popularity it did. Now having capitalised on OpenSource appeal you want to raise the drawbridge. Well you can't, it is TOO LATE. By all means retreat to your cathedral but the community already has a RIGHT to use the software you previously licensed. If you improve your database you will be able to restrict access to the improvements, but you have the rest of the world to compete against hacking on your freely licensed original, and after the political disaster of this foolish takedown nobody will be beating a path to your door. This is a REALLY dumb move and is only outdone by your insipid replies here. Do you think people in the community are idiots?