I've had one ZD1100 where I did something like this, but I have bad news: If you are seeing some sort of reboot loop occasionally which can only be solved by unplugging the hot-glued USB key inside the ZD1100, then you likely have a hardware failure of that USB key and need to RMA your ZD.
If you see this happening a lot, then you should RMA the unit.
(P.S. If you're tempted to try to replace the USB key, I'll save you some time: It doesn't work. The ZD seems to rely on that specific Winbond USB drive. Putting in another identically sized USB2 key, even with the exact same contents, didn't work)