We were wrapping up a combat when the party rogue stuck his head in the final chamber and started the final countdown. I'm not opposed to a grand finale, but we ending up missing a fair amount of exploration and basically got the scenario cut short.
My other concern was the minotaur. It doesn't fit in with the rest of the story flavor and in our case we didn't even end up encountering it due to us squeaking through with a minimum of clues. It would've made more sense for it to be some weird Frankenstein minotaur vs a ghost anyways. Plus, its appearance being related to the number of clues seemed arbitrary.