Default [Q] re-purposing the nook tablet button

i'm running cm-10-2 -NOOKTABLET-acclaim-HD on my 16gb nook tablet and would like to change what the lone hardware button does. It clearly supposed two types of button presses, long and short presses. It currently goes to home on a short press and to the task switcher on a long press. I'd like to set it the back button for a short press and home on a long press, thus allowing me to turn off the on-screen buttons and reclaim screen real-estate.

I tried modifying the gpio-keys.kl file, but whatever change I made seemed to just corrupt what the button did, injecting gibberish. Any thoughts?