9200 certainly uses a proprietary file system, and the second half of my post is the method I use for transfer (along with various software to read the Hummy HD and transfer to my host PC)
I haven't yet tried it with our newer 9300 but I also understand that it uses a Linux FS - this may not be correct though.
If it is correct, a Linux Live CD will allow you to read the files from the HD, if connected via such a USB adaptor as I descibed. Assuming a similar file structure, a player such as VLC or MPlayer would then play the TS files directly