Oh, and an afterthought - I've found with this particular tuner (especially if the batteries aren't brand new, or you're tuning an acoustic through the built in mic....) that it helps if you get close to the tuning you're aiming for by ear, then fine tune with the tuner.
For your Eb-Ab-Db-Gb-Bb-Eb tuning, presuming that you're tuning down from standard EADGBE;
1 - Tune the 6th fret of the bottom E string to the open A string (doesn't have to be bang on, just close...that applies to all strings.)
2 - Tune the open A string to the 5th fret of the bottom E string
3 - Tune the open D string to the 5th fret of the A string
4 - Tune the open G string to the 5th fret of the D string
5 - Tune the open B string to the 4th fret of the G string
6 - Tune the open top E string to the 5th fret of the B string.
Now you should be fairly close - press the flat button, hit the bottom E string - it should show "6E" in the top left hand corner of your display, and if you're lucky either the green light should be showing or one of the two reds, showing you're a touch out. Fine tune it, and repeat the process for the other strings.
Vic