MaxMSP/Jitter to LED Matrix - help or suggestions

Hi, I've been looking at taking the information from a jit.matrix object in MaxMSP and displaying it on an 8x8 RGB LED rainbowduino. However the only thing I've ever managed to display successfully on the matrix is the Rainbowduino CMD v2.0 program running on the Arduino. Yes I have tried the neophob libraries in Processing etc. but no success - just end up with a static few lights regardless of whether Processing is running or not. So kind of stumped at the first hurdle.

But please, any suggestion or comments will be appreciated. Oh and if you need to know I'm running OS X 10.6.6, MaxMSP 5.1.8 with an Uno and Rainbowduino.