Does Bootcamp support USB connections? Some virtual machine programs do not support USB, notably Microsoft's Virtual PC. A couple of them do say they support USB but not very well, especially if you have to use a driver that's really a USB-to-serial driver that creates virtual COM ports. That can be an exercise in frustration in a virtual environment.
It can be even more frustrating if the virtual environment or the CPU do not support hardware virtualization.
I wish I could be more helpful but I suspect that you and iNav corp. are up against the problems of a virtual environment rather than anything inherently wrong with
iGuidance.
When I built my latest computer in January I built a machine that would easily run 64-bit operating systems. I installed Vista Ultimate 64-bit, thinking that I would run Virtual PC or VirtualBox with WinXP installed in it for those applications that gave me headaches in the Vista 64-bit environment. After finding even more headaches trying to get those things to run in either Virtual PC or VirtualBox I wiped the hard drive and installed WinXP 32-bit.
A waste of a perfectly good 64-bit quad-core CPU and half the memory I installed but saved what little hair I have left.
For what it's worth, iGuidance runs rather nicely on my spanky new Acer Aspire One netbook. You might be less frustrated if you just dropped the $329 on one and forgot about the Mac. Shucks, you can hardly buy a decent personal navigation device for that kind of coin.
...ken...