Hi Hansine, I think you are at the part where you have to jump into a roundlike pool and in the middle of the pool is a pit. Behind that pit is a coffin shaped opening where you have to swim in and pull the lever. That will raise a bulls head above the water. I don't know if you used the patch allready but if not go to
http://support.lucasarts.com) and download the patch. After download doubleclick on it and it will find his way to your game and update it. After that start your last made saving and continu the game. If it still not works try pressing F10 and type: fixme. I hope it will work out but if nothing helpes, I must have a saving somewhere so mail me when you need it. Succes
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