I guess I'm stupid. I can't get beyond the first four rooms. I've got
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soap and marker
can't use any item on any other or on anything else. Can't find anywhere to go. And I feel really dumb because other people have finished this!
It's okay, I'm stuck too (can't figure out how to get the fairy dust). But here's something that might help you out.
If you go down from where the main hall is there are two other rooms accessible, one with a tin of paint and one with a kitchen. Open the fridge in the kitchen and take out the banana peel and mayonnaise. When you go back out you'll be attacked by a guy with a knife, use the banana peel on the floor before he gets to you. Take his knife and go dip it in the paint. Use the green marker on the mayonnaise.
and
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the knife on the soap
OK, thanks. Didn't realize there were rooms there. After you
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use the knife on the soad, you get something that's supopsed to look like a fairy. Enough like it to fool a dead girl, anyway.