Yet another foolish DRM scheme that will no doubt end up only hampering legitimate users in the end. Any cracker groups will disable this pretty quickly, now that it's public knowledge.
Don't take this as encouragement of piracy; I buy all my games, albeit usually on sale somewhere.
This reminds me of several past games that purposely crippled their software as a form of DRM, ala Titan Quest, that ended up mostly affecting people who actually bought the game.
Anybody who buys this game, and through bad luck of buggy coding, hardware issues, you name it, that experiences the Elevator DRM is going to have a major uphill battle getting these Croteam fools to fix it.
History repeats itself... again!