Id like to warn everyone: when you are in the canal room after youve defeated the guardian for the skull and you go up the ramp to the bridge above the waters, do NOT turn left at the shelves and try to jump over the collapsed pillar. you will be forever stuck in there. major map flaw. easy to get over the pillar, but you cannot ever get out. hopefully you saved as you walked in the door like i did, or you are going to have a bad time