As it turns out, the communication issue was a very simple one - there is an on/off switch near the top usb port that needed to be "off" and my board had it "on". It's possible I may have moved it when I took it from the package.
Note to element14: This switch detail should probably be added in the "troubleshooting" section (section 5.8) of the introduction pdf document.
So this is good - I have my WinXP VM running in VirtualBox on my MacBook, and it's connecting properly to the XL_Star board. Nice and convenient so I can play with this whenever I have a spare bit of time.