If you are playing the Developer's Cut version of the game, load the save in the Developer Mode version, open the cheat window (F11) and teleport to the start of the house, Exp_AC_Fighthouse_02 (in the 'goto Region' drop down list, it is about 3/4 of the way down; there are a number of entries for Exp_AC_Fighthouse with the numbers cut off, you want the third one.