grade puzzles from easy to hard to introduce users

Puzzles have difficulty levels (1-10), although admittedly they are not in order on the list. The CryptoPic Challenge puzzles start easy and get harder, though.

I did give textual clues to the Challenge puzzles and most of the other puzzles have either a comment or a title with a hint to the picture, although some of them are extremely cryptic as I have that sort of brain! In fact, I consider it a separate challenge for players to find the cryptic hints for the Challenge puzzles even AFTER solving them!

A hint button is a nice idea, I'll consider it.