Ok, from my point of view it's time to sum up some of our findings here and discuss them on a general (not too technical) level.
1) All interesting files on the DMS are signed
2) The DMS disk (its unique data like serial, etc.) seems to be signed
3) The firmware is checked by a non-accessible bootloader
4) Signed files are (compared to encryption) validated by public-keys only
These four basic findings lead me to the impression that it's going to be very hard to hack the DMS as these guys @Phatnoise (yes, I do mean you) knew what they'd done - no wonder, they're (were?) people like us! As long as we don't devise a way of using some still undiscovered bugs I can only imagine some hardware solution. We either might recode their initial bootloader (assuming it's an EEPROM) and/or try to manipulate the harddisk's firmware. Both of which I havn't done yet :-/
Time to discuss, and please keep it on a general level as the detailed technical means should be discussed in their respective threads...
Para