I'm not sure I understand how the traveller position effects the spi support. Sheet yes but traveller?
I have discovered that mainsheet tension seriously effects spi luff tension. I also found out yesterday that it's better to get the kite across and set before tacking (popping) the main in light airs.

Darryl, I think you may have mistaken my meaning. When I asked about jibing the kite I didn't mean tacking or jibing the boat. I note in the pics you sent me that your spi sheets run behind (aft of) the halyard which indicates that you tack and not jibe the kite on the AO.