Dougie uses an open C tuning for this song, and the Chords are mostly subtle Major7ths..

You can try a simpler G Am7 then (I don't know what this is called) slide up the Am7 chord shape 2 frets , and play around with those shapes...

I'll see if I can find more for you...

Some people (myself included) have been known to make a mess of this song.. :-)

StevenC