"Crazy"? "Insane"? Man, that sounds awful, it doesn't fit the "theme" of game.

Also, Europe level is easy, why is it now a challenge?

Overwhelmingly, the most common complaint I received about WarLight was about the difficulty of the latter three single player levels (including the Europe one).

Despite naming them Challenge levels and describing their difficulty in the yellow bubbles, people still felt like they needed to complete them before trying multi-player. Rather than making the levels easier, the name changes are attempts to communicate the expectation that these levels aren't something that you just play in order in a single sitting.

Further, the ending of Level 3 received some changes as well. There's no "Next Level" button that takes you into the challenges, instead it explains how to get started with multi-player. This is supposed to signal clean break into a different mode of levels.

Overall I'm hoping this sets expectations and reduces the complaints I hear about the difficulty.

Okay, I understand your point; but still, I think Europe is really easy (and I'm not a top player, mind you; and I just re-played it to make sure that wasn't pure luck), and any problems that anyone might have had with it probably come from not using airlift cards, or not knowing you can airlift reinforcements to ally - maybe just bold that part about them in the introduction, or something.

And I'm not against naming the challenges something else than "Challenge #"; I just dislike the names you've chosen. Maybe use some less "crazy" adjectives - for example, "Impossible", or some synonyms: http://www.yourdictionary.com/synonyms/impossible - just think about how "Inconceivable" or "Hopeless" sound, and how apparent it is that such levels are barely passable. Also, http://www.yourdictionary.com/synonyms/difficult - "Ambitious".

I hope you'll use my suggestions :D

Maybe name them after famous military commanders. Alexander, Pershing, Attila, Bonaparte, Patton, Jackson, Rommel, Khan, etc. Not sure how to map them to difficulty though.

I don't mind the new names. I kind of like them.