I'll take a shot at this for you mike, although I must confess it took a while for me to figure out what the hell I do!
Not instilling confidence, am I?
Alright. While my key references may (or may not) be off it's the notes that are the thing.
First here's the chords.
D Dmaj7 D7 G Gm D A G D G A D A D
Over the D and Dmaj7 --- D ionian
The D7 ---- D mixolydian
The G ----- G ionian
The Gm ---- G minor (Harmonic minor?)
For the above just drop the third a half step in G ionian. (B to Bb)
For the rest I play D ionian although I also put in mixolydian over the G at times, expressing the C note.
Hope this helps.