Now this is an evil one. I would tend, as others have mentioned, to give more hints early on, but thats my own take.
A great plot!
A great start to an adventure, or a really good complication to an ongoing one...
A good basic plot and could, as manfred said, be a good campaign start location.
This strikes me as a good prologue, but some help on what to do next might be in the offing. A lot is left as an exercise for the student :)
An adventure to use with great care. I'd only use this if restoration was reasonably possible.
I like this idea - a decent reason for a dungeon to exist. And loads of fun all around.
The only weak part is the assumption the PC's are master builders. :)
A nifty little encounter.
An interesting Idea that I had also used - though I had not seen this post at the time.
A good basic idea that could easily be broadened into a great adventure!
A decent adventure start.