OK I sent this guess to Steve with the pic since we were all sitting around trying to make sense of the symbols or if it was just a random design. Not the best pic of Steve but it was the best of the Rok, in his defense the wind had died and it was shot from 80+ yards away without his knowledge as he was walking it out of harms way since a group was starting to play soccer just yards from it.
We all saw the birds in the outer circle, I saw them as an Antelope also if you look at them upside down from the bird. So that covers 2 out of four of the elements - Earth, Air, Fire & Water. Lets fill it out with the center sections, the left one in that shot I can definately imagine as Fire so that leaves Water. I could imagine the right one to represent a Jellyfish, Squid or Octopus so that covers Water. The centers also look like a Spirit or Angel if you want to include a fifth element of spirituality.
Now what use are those vents at the cross of the spars? If Ty went to that much trouble they must mean something since they certainly are not functional. Notice all the elements are coming out of those vents, coming out of "Nothing" as in the Big Bang theory or alternately and ideally the Sun would be shining through those holes so they are coming from the Sun as many believe.
I know, I know ... but I was not under the influence, a flashback from 30 years ago could be a possibility though