This posting has been read 100 times since February, but no one from Peterson (or anyone else) has responded. There has also been one other DADGAD question posted, with one reply from the Peterson representative (offering no real help).
DADGAD is a pretty popular guitar tuning these days. Peterson has posted tuning offsets for 6 open tunings. I think we need a chart of recommended offsets for at least DADGAD C Major and DADGAD D Major.
I'm hoping that someone a Peterson is monitoring this forum and will respond. But, it's been 5 months since this question was posted. So I won't hold my breath.
Please bear in mind that although the forum is for general discussion and we do our best to answer all questions thrown our way, ultimately our time is limited (which is one reason why no other tuner manufacturer does this). The open tuning offsets were recommended for slide/resonator/dobro because fret-board action is not an issue. With modal tunings like DADGAD however, success would be contingent on excellent action on acoustic guitar, which is not always the case. You yourself can find a tuning which sounds ideal and duly measure and record the offsets for your particular acoustic guitar, that was the intention behind making the tuners programmable. We will be sending out helpful tips on this and other tuning offsets to our users in future editions of "Tuning Tips".