Fixed BDEX bit in track_thin where a lookup of block elements in a single element array was done (i.e. negative index).
Fixed BDEX bit in track_thin where a lookup of block elements in a single element array was done (i.e. negative index).

SixTrack/SixTrack,SixTrack/SixTrack,SixTrack/SixTrack,SixTrack/SixTrack,SixTrack/SixTrack,SixTrack/SixTrack