Aztec is famously easy to root, and I've heard Kauka is just the opposite. Not sure about Katie, though. Rainbows in general can be quite difficult, like reds.

Hey Moonie,
I brought back 2 cuttings of Kauka Wilder from the Black Sand Beach on the Big Island Hawaii and had them potted for 6 months before the first leaves showed up! But boy am I glad they did.
You need to be patient with them and yes they are slow to root and the reward is worth the wait!
Here's some of my photos of Kauka Wilder I planted in August of 2011:
Leaves started to show in March of 2011

Jen - I knew that reds were hard to root and now I can add rainbows to that. I did not know. Thanks!

Stuart - Beautiful pics, and definitely it looks worth the wait so I will practice some patience knowing that it's normal for KW to root so slowly. It's a little bit scarey though, afraid something is rotting somewhere. LOL

To be honest with you, I just stuck it in the pots and left them alone other than brought them in for January & February and back into the sunshine in March. The trees they came from were so old and weathered but I was able to find 2 healthy cuttings. I saw some broken limbs that had rooted right into the ground as it laid, sounds cray but true!, but then again anything that touches the ground in Hawaii will grow!
So yes, practice you patience and don't baby them and they'll surprise you too.