DGDGBD Tuning help

I love this tuning. I just started messing around with open chord tunings. Why arent they taught? They are fantastic epecially when it comes to playing I IV V progressions. My question actually is how to play other types of chords with this tuning. What about extensions like 7ths and maj 7ths and so on? What about scales, are there any patterns and such.

Thanks so much for all the help.

This site will probably help you - it has loads of stuff.

Click'ms