1) Yeah you may be thinking of the
Mega X Key. Or there are homemade versions. You can use these if you want to.
2) I cant see which pakage you have so can't be too specific about which files you have. As long as you have an official release (from Smdepot.net or #xbins) then yes.
3) 1.6b, will not affect your softmod too much. Also PAL is the best region of all because im there... and with reference to playing other regions games and video, you should be able to do this no worries when your xbox is modded.
If anything is unclear or if theres anything else just ask some more.