When You Get Into The Maze To The Flooding Room At The End, Instead Of Going In The Door To The Chapter 2 Location. There Is A Vent Located In The Flooding Room... Just Open It And Enter And You Will See You Are In The Classic Mansion. Then You Know What To Do. The Flooding Room Is After The Maze...
Just Find The Key Inside The Mansion!
Once You Find The Key Go To The Front Door Then You Are Done!!
It Is A Bit Difficult Then It Looks.
ENJOY!!