Guided Access - Restricting the Back button

The Accessibility feature of iOS6 for iDevices has given us the great gift of Guided Access which will disable the Home button and essentially lock the user into an app. There is a second function that Guided Access offers, and that is to disable touch access in a particular area of the screen. I have used the "disable touch" feature when introducing a new page of vocabulary in an AAC app or in educational game play where I want to limit access to the game settings or an on-screen skip ahead button.
 
When starting Guided Access, you will be brought to this screen - an image of the app in play with a frame of options around the sides. The instruction just below the screenshot reads "Using your finger, circle areas on the screen you would like to disable." In this image, the user has circled the Home button across the top of the screen. The iPad recognizes your imperfect selection, and snaps it to the border of the touch-sensitive area or button you intended. At the upper right, select Start, and the disabled area will be visible through a translucent gray shade. 
 
To lift the restriction, triple-click the home button and enter the passcode, then use the "X" in the upper left of the shade to remove it, or End Guided Access all together using the End button in the upper left.

Some third-party apps have a bug with this feature that cause them to lock into Guided Access (meaning the triple click of Home doesn't offer the prompt for the passcode). Scroll to the bottom of this post (HERE) for a workaround. Hopefully iOS6.1 will have a permanent fix for this bug.