Even more hints:

Level 01: Look at the picture. The answer lies in the dark.
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Level 02: You allready have y. What you need is x. What and where is y? Look on the source code. X and Y is of the same kind.
What does Y reminds you of? A cold dark winternight maybe? Or something else?
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Level 03: Up high in the sky. Whats the name of the photo?
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Level 04: My gramma has never been that good... And whats with the soldiers?
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Level 05: That's a wierd title, isnt it?
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Level 06: Aha.. thats is what is supposed to be... Why is picture so large, and what is "where the sea meets the sky"?
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