I also kind of want to know WHY Kakashi stabbed Rin, but that's probably going to get explained during Kakashi's fight with Obito.
Also I don't think Obito revived Madara with it because he already saw the 6th coffin by that point and new Madara was in it and that the Impure Resurrection was better. And that if worst came to worst he could just re-revive him later.
Oh, and the difference between the stole and gave thing doesn't really make a substantial difference, either way he got the eyes and his brother died.