An always fun, short experience to be shared here and a slight bit of generic advice. That being, Dungeon Masters, never make any puzzle or event too complicated. If your party is spending two hours on a puzzle, it is probably outside the scope of reasonableness, even more so if said puzzle is woefully complex, involving stepping on the right tiles, going down the right hole, arranging the right letters, and then knowing the Dungeon Master's birthday - something none of the characters reasonably know themselves - and dealing with two doors, one that always lies and one that always tells the truth. Then, when we catch you on that last one and ask what color red is, the doors do not suddenly fall silent and teleport us back and make us restart the process. 

As such, please do not act surprised or angry then when someone with the ability to ignore object hardness, say with the [i]Mountain Hammer[/i] strike, decides to just bust down the seemingly impenetrable doors and starts smashing holes through the walls to just keep going. Some of us would like to play the game.