Hmm, it was originally a little easier, but I ended up making it harder. I didn't have too much trouble while playtesting it without secrets, but I do agree that it's a bit of a difficulty spike. The development of the map was spread over a month or so, and I ended up going all the way from start to end of a going down replay, so... there's your explanation of why it got so much harder :P. I'll try to keep the encounter difficulty a bit more consistent in my future maps though!
Also, sorry about not really responding to anyone, university has been busy and I haven't had much time but I should have some more time to watch demos soon.