>I am having problems with the quest given by the Imp "Horex" for the rat tooth
to help save the other imps life.<
Past some doors that are opened with levers - you need to split your party up to get past. There is a room that you probably couldn't get into - you need to shed some, er, darkness on the door. The hatch is opened after you get the monster (not rat) tooth for the imp.
>The other quest is How to prove to the ghost in the secret area
in the original cellblock that he is dead?<
You may recall a rat in a room not far from the ghost died and dropped a large bone. Hmnnn. Maybe the ghost would know he was dead if he boned up on the subject.
>Where is the arena with the monster cages. I need to kill some rats there fer another imp in the last level of chapter one.....oh well thats 3 quests..<
You don't need to kill rats you need to pick up a book that is hard to see next to a pile of hay. The arena is where you jumped down the hole to get to the level where the imp gave you the tooth quest.