The good news about the USB is that it is a really general method of communicating with devices. This means it can be used with all kinds of devices.

The bad news, of course, is that if can be used with all kinds of devices.<grin/> There's always more protocol on top. Kind of reminds me of the old days of working with serial ports.<shrug/>

If and when you get the technical docs, you might want to consider releasing a Perl module on CPAN. That way you can save someone else from having to work this out.