Sorry, I might have used the wrong word - by 'pushed' I meant forced on me. Preventing Amazon updates will be a good idea. You guys were really quick in dealing with the last (quite tricksy by the look of things) update - but who knows what amazon are going to do in the future.
Your ENABLE_HACK_UPDATES file idea looks great. You mean a bin file I presume? (I can just create them using gedit, but I want to make sure I get it right).