It worked pretty well. I kind of misunderstood the rolling boulder trap, but what I did in my confusion worked out okay - I just reversed the direction it travelled, so that it headed for the characters as they came in the door to the room (what I should have done is have the kobolds trigger it when the PCs were on the other side of the central enclosure, closer to the wyrmpriest).
A well placed blinding barrage (and totally not as useful for the next encounter) and great rolls ended up blinding 2 kobolds, the wyrmpriest, and the drake. The rest of the characters had great rolls the next round and were able to finish off the drake and 2 kobolds leaving the wyrmpriest who didn't even get to use his leadery abilities as he got wasted. The ones in the center room couldn't come out and assist fast enough and though the party got hit hard with the boulder and a few choice attacks, it overall lasted WAY too short. They loved it though... and the rogue really felt super useful in exactly the sort of way I'd like a rogue to.
My wife found the immobilising dart traps in the second room frustrating, but in the right kind of way, where she was excited when she managed to avoid them and smash the statues to shut them down.
Yeah, it was a nice example of a simple trap, especially for groups that have given up on traps in the past and would like a quick reintroduction.
The skull-skull stone "trap" in the third room was pretty funny but not very effective.
IF you mod anything, I'd mod this one... it was very fun to describe and the players enjoyed the thought of it, but it didn't seem to hit as well as I wanted and they were able to range kill the kobolds above a bit too easily. I Tried to have the doors remain shut and hold back a bit, but I think perhaps it would've worked better with more targets early on and perhaps the pool being larger and longways to allow more easy pushes into the pool. The party wized up even before they got hit that they'd be pushed (quickly they've learned the 4E mindset, huh?) and kept to the side walls to avoid this. Curses!
The final fight was tough, but she survived without losing a single PC.
I quickly felt that they were in trouble with everybody dazed (?) from the breath... so I tried not to run it TOO nasty without cheating the next 2 rounds only to find the party got him flanked and was doing better, so I pulled out all the stops with a nice recharge, did everything I could to waste them all but couldn't do it. Dailies hit well and while effects didn't play into it as much as I would've preferred, they were able to do some useful things and take him down.
I suggest that if you're planning on running an adventure here, you allow a hook to begin with this encounter. We're doing H1 so as they entered the secret passage I described a much longer winding passage than is indicated in the map and allowed them to overhear a conversation between two dark voices as they moved downward. It basically set the stage for H1 with Kalarel thanking the Dragon (I tried to spell the name from memory and rolled a 1) for his assistance with the last piece of the parchment and delivery of a treasure chest for the dragon as well as promises to have all the treasures at "the site" once he was able to unlock the door (to the second level of the keep). He bade the dragon farewell and then disappeared through an unknown means. The players entered the chamber to find nobody and began exploring for a secret door when WHAM....
I don't necessarily think it's anything super crazy or exciting for an experienced group, but a nice intro with several combat features in play for a new group or a quick run through with new rules for some veterans. Nice thing to do on a saturday afternoon.
It should put characters just below level 2 which I'm hoping will allow them to hit level 2 before the irontooth encounter in H1.