I have a feeling on how this ferrox loader works, too bad im not able to write scripts or compile a kboot, otheros.bld file, or i might be able to help you all out.
what im guessing from this video, is that their own otheros.bld file was compiled, and isntead of the boot loader being told to run linux, it was told to run a specific program from the linux directory, wich will then in turn load up and in the script have the option to load an iso file, with the "autorun" option so to speak.
so it would look like this in a way:
put the new otheros.bld in the usb stick, restart, iso loader loads from the otheros.bld file wich tells it to look in a certain directory. and then scripts tell the loader from that directory what files to load.
this is the only way i can see a loader working on all firmware.