I’ve posted some variations of the Demo sketch on the Arduino forum that you might want to check out:
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1273413449
There is also a discussion in the Arduino Syntax and Program section with some interesting info regarding methods of freeing up RAM and alternate code. The link is:
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1267698132
I bought the Stalker and UartSB from RobotShop and they have been very helpful and have responded to my questions quickly. They also have Stalker documentation or their web site.