My nook received an auto update from B&N on 12/19...I didn't think anything of it...I already had a sidebar with other apps. Yesterday I was downloading books from the kindle store on Amazon via desktop and everything was working perfect. But when i tried to download a different app from the Amazon app store directly from the nook tablet I received an error "Install Blocked" For security reasons, only apps purchased through the Nook shop can be installed". So now i can not download any 3rd party apps anymore...what can I do to get rid of the B&N Update?