Ok I just had my headset go into bootloader mode and had the same problem. I was also getting the same results as the guys above me. I would follow the instructions posted and go to fimware up date and try to update my headset and it would just sit there and do nothing.
I saw an earlier post saying when they are in bootloader mode they are actually on.
So what I did was unplugged them and let them sit for 2 days letting them die completely.
Then came back here and followed the steps and it worked just fine...
What I did
1. Open Cue
2. Go to settings
3. Update firmware
4. When it asks to plug them in this is the first time I plugged them in! From letting them sit for 2 days.
5. The fireware actually went through and I got them back up and running.
So I am thinking the key is to let the battery go to 0%