Hey Glynn,
Sorry to hear about your nasty problem, because it seems something with so few to do and taking so much time to test (reboots, removing the card again, etc.).
Assuming you use V1.07 for the driver (which will be the latest, unless there is a recent new one), I would try 1.21 (which is way older, depsite the higher number !). There's also another one which works for W7 and what we do with it, and Roy mentioned it somwhere (in that thread where I anounced that the Juli@ can do Kernel Streaming allright :
So, a Juli@ doesn't dig KS, right ?).
Next think about some possible problem with the buffer size, and that it may run on some size which is not the default (IIRC the default is 128), BUT that it won't store your change, and thus at a reboot falls back to that size at which it won't reboot at all. A bit vague maybe, and theoretically even impossible as the cause if you read well what I wrote, but still a kind of explanation for "it has worked a few times". On this latter, think about how it will work the very first time, where at booting it can't do anything because it is not known. This "not known situation" however, only exists when the active driver has been removed, and in the thread I referred to is mentioned by me how to do that. So, next you can boot with the Juli@ in there, and now you can appoint your (own) driver (see description in that thread again), and ... this already may do tricks because possibly you didn't do it that way before.
If this doesn't help by itself, set the Buffer Size to e.g. 1024, and check a couple of times whether it's still in there. If yes, reboot (yeah, you will be 30 minutes further already, I know). If this helps, and you can determined it is the buffer size by setting it back to 128 and reboot (and then it dies again), never set it to 128 anymore.
Btw, the story about the buffer size is way too long, looking at the chance it is the cause. It is just a very wild guess.
Good luck now,
Peter