Challenge 6: JAVA BREAKING
As much as I'd want to say Java is already broken, that's the challenge and you've got to get it done. .jar file provided - can't be sure it won't run malicious code on your computer, of course, but the idea of this event is to have fun and we gotta have sure you will.
Challenge 11: .EXE CRACKING 1
What will take you longer - downloading this executable or cracking it? Could go either way.
Challenge 12: .EXE CRACKING 2
Unless you have a really slow Internet connection, the answer to the previous question is no longer "downloading".
Challenge 13: .EXE CRACKING 3
One more. Unless you've been there before, good luck to you. Oh whatever, you'll need that anyway.
Challenge 14: .EXE CRACKING 4