How quickly does the iron rot? Everyone still has metal weapons, and those must take a lot of effort to make. So it can't be too quick. And why doesn't armor crumble as well? Or wagon wheels? Or buildings and bridges?
If evil kobold terrorists are trying to bring down Amn, wouldn't they be better off sending out a shipment of rotting nails and watching the Amnish (Amish?!) infastructure crumble?
Isn't the bigger problem the fact that bandits outnumber farmers 30:1? Or that the entire economy is based on inns, carnivals and arms merchants?
How exactly does the ecology work? What do all the bears eat? How are there polar bears within an 8 hour walk of the desert?
There's a haunted wizard school. Some curse, etc. The upper level is all roaming undead. Makes sense. But the basement is packed with wolves. First, since the undead are either a) unintelligent or b) incorporeal, the basement must've been built as a dungeon while the wizards were alive. Which is already a little distrubing.
Where did the wolves come from? Are the wolves the 10th generation of trained wizard-wolves, like Michael Crichton's Congo? And why would the skeletons be on the surface and the wolves underground? Do they sprint by the skeletons every night to go get food? What food do they get? Do they eat bears? Do the skeletons not attack the wolves, or are they just too slow to catch them?
How are there primed fireball traps in the dungeon? Have they been there for hundreds of years (and why would the wizards put them there in the first place)? How do they wolves avoid the traps? Why isn't the "basement" just filled with the centuries-old remains of barbecued wolf?
How cool is it that there's a character named Jared?