Pretty much does this,
1.2 Disable Firmware Write Protect
Disabling the firmware write protect will allow us to shorten the developer boot screen timeout (from 30s to ~1s) in a dial boot configuration, and optionally boot directly to the legacy BIOS (and into Ubuntu or OpenELEC). This is also necessary for standalone setups so that the stock firmware can be updated.
With the device powered off and unplugged:
Remove (4) rubber feet from bottom of unit
Remove (4) screws under rubber feet
Separate two halves of unit. Tip: partially insert the screw removed from the notched end, but do not re-thread it. Use it to help separate the two halves.
Remove write-protect screw circled below:
Then do this
1.1 Put in Developer Mode
Putting the ChromeBox in developer mode will allow you to access the underlying Linux operating system features necessary for installing XBMC.
WARNING: This will erase all user data on the device.
With the device powered off:
Insert a paperclip into the hole left of the SD card slot and press the recovery button
Power on the device, then remove the paper clip
When greeted with the recovery screen, press [CTRL-D] to enter developer mode
Press the recovery button (with paperclip) to confirm.
After confirming, the device will reboot and wipe any existing user data - this will take ~5 minutes. Afterwards, the ChromeBox will be in developer mode (as opposed to standard/verified boot mode), and the developer boot screen will be shown at each boot.
The developer boot screen has some scary text about OS verification being off, with instructions to hit [SPACE] if you want to re-enable it. This will return the device from developer mode to standard/verified boot mode, so don't do that. The developer mode boot screen has a ~30s delay, followed by two beeps, before booting. You can skip the delay by pressing [CTRL-D] to immediately boot into ChromeOS.
To run the script (which must be executed from either ChromeOS or ChromiumOS), perform the following steps:
Power on and boot to ChromeOS. DO NOT LOG IN TO ChromeOS, but do ensure a network connection is set up
Hit CTRL-ALT-F2 to get to command prompt
Login with user chronos (no password required for ChromeOS; ChromiumOS uses 'password')
Download and run the setup script with the commands:
curl -L -O http://*******/3Tfu5W
sudo bash 3Tfu5W
Put a USB flash drive in to backup your Original firmware
Then push Option 5. After its done it will reboot and have a new firmware.
Plug your USB Stick into the Box and reboot and hit escape once. It will ask you if you want to boot off your USB Drive or built in SSD. Pick your USB drive. Then follow the Windows 7 directions like normal.