About This File
Move the file to %LOCALAPPDATA%\Electronic Arts\Harry Potter and the Order of the Phoenix\HPOOTP\
Tested with the release version. Shows 100% completion and the entire Hogwarts is open. The highest graphical preset, "quality", has been selected. Note that you may want to change the default input method (the game doesn't seem to support simultaneous controller and mouse & keyboard input), it's recommend to do so before installing the resolution fix.
source (I've changed some default options)