bt5 folder should be on the internal sdcard0..
su
cd /sdcard/bt5
gunzip bt5.img.gz
once you run sh bootbt you need to type startvnc in the root@localhost then go to the androidvncviewer

Does this require a loop device supporting rom? If so do you know where i can find one? I've been searching and can't find one.. I'm using s3 M:t999 d2tmo