I can't help with the total fix here, but the Nook Color App Manager is a nice low-profile B&N/Android switcher. Pulls up a 'Use this Launcher' menu. You should at least be able to access the android side this way.
https://market.android.com/details?i...loadapps&hl=en
http://forum.xda-developers.com/show...44&postcount=8
Check out the XDA forums for your 'n' button fix - I know I've seen threads dealing with the issue.