Battlefield key #1 is susposed to be North of Cassandra's house, in the large cemetery in one of the graves. I've been to all the gravestones I can find, but none of them has an item inside. I've also used the Alt. key but nothing highlights!?
Nevermind I have found the Battlefield Key #1. This game is really touchy. If you're not exactly on the spot it wants you to be, you'll never find anything. Close only counts in Horseshoes!