"Searching for clues" - help needed

Hi!

I have been designing this game with the help of a couple of friends for a while now. Its mechanics are pretty complex so I won't be going too deep into it right now, but I do need help with one aspect of it. I'll just explain everything you need to know in order to help me - if you happen to feel like doing so. I appreciate any constructive comments even if you couldn't give me a solution here.

I got the idea for this game when I was thinking what kind of game would it be, if I was to combine Arkham Horror / The Mansions of Madness and Afrikan tähti ("The Star of Africa" or "Diamond Hunt" - a popular Finnish children game). The game is set to an alternative present, where a group of people (the players) arrive to a mystic island (the game board) in search of an old relic that is told to hold omnipotent powers. Obviously, there are going to be obstacles but they do not concern this particular topic.

In order to find the relic players are looking for, they must follow [i]clues[/i]. Clues are a deck of cards which is shuffled in the beginning of the game. Then a certain amount of cards are picked from the deck (the amount depends on the amount of players) and others are put aside from the game. The first clue is revealed at the beginning of the game. The clues tell players to go to certain locations on the game board and then do a certain kind of action there in order to find the next clue. The one who solves the last clue will find the relic the players are looking for - and though it won't mean that he or she has won the game, it means that he or she is pretty close doing so.

I see two problems here.
1) The game is not co-operative (well, not completely at least: the players have a common enemy but only one can truely win the game by taking control of the relics power). So, when someone solves a clue, it is kind of odd that every player would get the hint where the next clue is found. Then again, I believe the game would get too messy if every player had to solve every clue.

2) This is the more serious problem. If solving the last clue is the only thing that counts (after solving the last clue you get the relic), why would anyone bother solving the earlier ones - especially since they might make your character hurt or things like that? Should there be some kind of prize after every solved clue? Should solving at least one other clue be a necessity in order to gain the relic? Should solving clues require some work from every player? A combination of the things I mentioned or something totally different? At one point I played with the idea that every player would begin with one clue of their own and work their way from there, but I'm not really sure if that's a good idea either. Every player would be just "playing their own game" and not paying any interest in other peoples actions - and to me the company of other people is the best property in board games.

If you have any ideas, I'm willing to listen :) And if not, thank's for reading anyway.