Who says pure evil cannot create good? I didn't see any rule book that states before creation God can't be pure evil and all powerful. If that's what it is - that's what it is.
Now if that pure evil God wants to conjure up some stuff that sure looks like "good" to us mere mortal humans, it wouldn't take him much at all. He just has to think "illusion of good", and then blink his eyes and there it is.
As for free will - what is that other than one more thing the evil God gave us to help our torture in hell in hell for believers in his fake Magic Book will be all the more sweet? "Heheheh! I gave them 'free will' and now the idiots must think I'm a good God!! They're so stupid!"
Because there is good in the world it shows that the evil God wanted us to be thoroughly tricked by his illusions of good. There had to be truth before there was a lie, and that truth was pure evil.
Well, it's your make believe world, I guess you can make up the rules as you go along. I'm done playing this game.
Remind us again, are you a Christian or not? If you are, what's the point of taking the atheists' view? Do you think this forum is like a junior high debate class and you picked the "anti" side? Just for the record, I understand that this is real life and that real people read these forum threads and real people's eternal destinies are on the line. Did that occur to you?