@Rei_Ayanami : I dont want to sell the game its just a Fan Project and freeware , i know i need the rights to sell this.
This looks like great amount of work. It would be really bad if you have to stop it later on.
They can also stop free games if they want to. It is their copyright and nobody is allowed to distribute their IP, no matter if you make it free or not.
The best way would be to ask them right from the beginning.
